This story first appeared in the Oct. 9 issue of The Hollywood Reporter magazine. To receive the magazine, click here to subscribe.

"Columbo, come on, boy, come on, let's go!" The 125-pound, 5-year-old Cane Corso, its obsidian folds of fur arranged in curled repose, just won't rise from the floor. "Come on, boy, come on, come on!" Arduously, Columbo finally obeys his owner, right hind leg limping as he lopes forward. "See how he's dragging that leg? Watch his hips, too. This is the behavior of a 12-year-old dog, not a 5-year-old."

Columbo's owner, cheerleading captain and injury analyst Tyson Kilmer, also is one of the go-to canine-aggression trainers for the entertainment industry (his clients have ranged from Tom Freston and Mike Tyson to Joni Mitchell and Rob Lowe). On a quiet September afternoon at his rambling home and training compound in Encino, Calif., with Columbo at his feet and his wife and business partner, Alison, at his side, it's his own aggression that he's trying to keep in check.

In what's emerging as one of the most peculiar estate battles in recent Hollywood history, the couple claims they've been left high and dry by the trust of the late Simpsons co-creator and animal rights philanthropist Sam Simon, their close friend who bequeathed them his troubled rescue dog after his death in March at 59 from colon cancer. The trouble is that the Kilmers got the dog but not the funds they say Simon verbally had promised them to maintain Columbo's estimated $140,000 annual medical and therapeutic care regimen that includes, in only-in-L.A. style, twice-a-week acupuncture that costs $3,640 per month. Simon, whose fortune is said to be worth several hundred million dollars, paid for this regimen until he died.

Simon (far right), with fellow executive producers of 'The Simpsons' Matt Groening (far left) and James L. Brooks.

For its part, the trust, overseen by Simon's former business manager, paints Tyson, 46, as a shakedown artist, alleging that he requested $1.7 million and then demanded a lump-sum payment and threatened to "go to the press" if that was rejected. (Tyson did not initiate contact with The Hollywood Reporter; this story emerged from reporting into Simon's posthumous philanthropy.) "It's a stick-up," says the trust's attorney, Paul Sorrell of Lavely & Singer.

The Kilmers aren't the only animal lovers feeling wronged by the Simon trust. Several prominent nonprofits, including People for the Ethical Treatment of Animals, which had grown to rely on the producer's largesse while he was alive, say they have gone unexpectedly without his support since his passing, despite his verbal assurances to them that his trust would provide for them. These groups now are coping with the discrepancy between how he had expressed his wishes for continued patronage of their causes while he was alive and how the trust has communicated and demonstrated its support.

"In my opinion, there is something quite irregular with this development," says Capt. Paul Watson, the head of another organization, the Washington State-based Sea Shepherd Conservation Society, for which Simon provided the funding for a 184-foot anti-poaching ship it christened the Sam Simon. "A failure to follow through with Sam's promises and stated commitments will only serve to tarnish the unblemished reputation of this remarkable man who is no longer in a position to defend those promises."

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The Kilmers say they've been unfairly financially burdened by adopting a .001-percenter's pet. "It's a staggering amount to drop on a couple who have two kids — one of whom is special-needs — and are running a small business," says Tyson. (The trust doesn't dispute that Tyson was named in Simon's will as Columbo's caregiver but asserts Simon also named a properly trained backup person to care for Columbo who was willing and able to do so at no cost.) The Kilmers refuse to give Columbo away, out of loyalty to Simon as well as professional obligation. Yet the financial realities of this dispute may lead to the suspension of certain care services for Columbo, who, if not for Simon's wealth, would long ago have become what's known in animal circles as a "death row dog," a hopeless case who would be sent to the pound without prospects for adoption and eventually euthanized.

The potential decline of Columbo's care regimen could, the couple insists, quickly lead to a regression in his behavior, yielding vicious, even lethal, consequences — with their on-site staff members and young children at highest threat. The Cane Corso is a descendant of a legendary Roman war dog, a mastiff breed that some people consider a pit bull on steroids. Though Tyson says Columbo is "sweet 99 percent of the time" (happily greeting this seated visitor with a chin-to-nose hello lick), he is fundamentally "a very dangerous animal" — an animal with an early-life history of physical and emotional neglect at a suspected drug dealer's property. (Simon plucked Columbo from his dog-rescue foundation's shelter after he was found in a chicken coop.) His record includes biting incidents and attempted maulings, the kind for which "you can't have one mistake, because it will change your life in an instant."

Tyson Kilmer with Columbo, photographed by Claudia Lucia on Aug. 12 at the trainer's home in Encino.

The executor of Simon's private trust — his business manager, Julie Miller of West L.A. firm Holthouse Carlin & Van Trigt — declined to be interviewed for this story. She did, however, describe the extent of her relationship with Simon in a conversation with Jordan Riefe, another writer for THR, during a brief Sept. 16 phone call for an unrelated article about an upcoming Sotheby's auction of Simon's effects. "We met several times and we communicated mostly through text," Miller said.

As to the current allegations, Miller opted to have top crisis PR specialist Matthew Hiltzik send THR a statement, which notes that Simon "carefully planned every detail of his trust and worked with an independent philanthropic adviser to maximize the impact his estate had on charitable causes that Sam cared about." The statement also says Miller "allocated reasonable resources for Columbo's care within the limitations allowed by the trust and the law. However, these generous contributions were met with endless frivolous complaints by the trainer that these funds were insufficient." In a subsequent conversation, Hiltzik and Sorrell insisted that there were no financial provisions for the dog's care in the trust documents, which they declined to make available for review.

The statement goes on to argue that Tyson's complaints "were even more outrageous" given that "there are others that Sam had selected willing and able to look after Columbo at no cost." It reads: "Nobody is forcing [Tyson] to take Columbo, or to spend excessive amounts of money on his care," also adding that "instead of thinking about the many animals that could benefit from the full allocations from Sam's trust, this individual has instead put his own selfish needs ahead of Columbo's and other animals whose lives can be saved and improved by Sam's donation."

The Kilmers, who assert that Tyson is a named beneficiary, have a different take — saying that Miller told them that the backup person was an instructor who resides at the Sam Simon Foundation, a facility that Alison says lacks the ability to handle big, aggressive breeds. "They will put him in a cage," she says. In a 2007 60 Minutes segment on Simon's philanthropy, Barb Velasquez, the facility's chief trainer, conceded that it can't handle dogs that are too big or aggressive: "The hardest part of all this is looking at a dog that you know is not at all suitable for our program."

Where things have gone sideways in this dispute is impossible to determine. Enormous estates often are a swarm of fights and misunderstandings and claims of broken promises. Simon is gone and the trust won't share the key details it harbors regarding his intentions; while not prohibited from doing so, it certainly is not obligated to respond to anyone but a judge. Its detractors may assert that Simon's wishes aren't being followed, but it's possible his wishes are being executed just as he specified. Regardless, many people who knew Simon best are disturbed by what has transpired.

"The notion that the organizations that Sam dedicated so much of his life and fortune to should in any way be cut off is sickening," says Mark Thompson, a close friend and radio host on L.A. classic rock station 100.3 The Sound. "Sam had clearly intended that they continue to be fully funded to do critical work. The whole thing is bizarre. Throw Columbo in the mix, and it takes an even more twisted turn. If this is all true, then Sam's estate is being administered by people who have no consideration for who he was and what he wanted his continuing legacy to be."

Simon's business manager turned executive trustee Julie Miller.

•••

Simon, a comedy veteran (Taxi, Cheers, It's Garry Shandling's Show) who won nine Emmys, made his fortune from The Simpsons, which he helped create by staffing the original writers room and developing such key non-family characters as Mr. Burns. More specifically, he secured a lucrative negotiated payout in 1993 — after he clashed repeatedly with Simpsons co-creator Matt Groening (who called Simon "brilliantly funny" but "mentally unbalanced") — that locked him into hefty and still increasing annual sums for international syndication.

While he continued noodling around in the business, working on shows for George Carlin and Drew Carey, Simon primarily began involving himself in manly sidelines — managing boxer Lamon Brewster to a World Boxing Organization heavyweight championship in 2004, finishing in the money several times at the World Series of Poker — and pursuing an interest in deep-pocketed philanthropy focused on animal-rights activism. The vegan would host an annual celebrity-studded fundraiser for PETA (the organization wouldn't provide details of his donations but noted that it named its Norfolk, Va., headquarters after him) at his lush 1.5-acre property just off the Pacific Coast Highway in Pacific Palisades, and in 2002 he launched the Sam Simon Foundation, dedicated to rescuing and retraining canines who, like Columbo, would otherwise be euthanized. 60 Minutes described the 6-acre spread in Malibu as "the grandest dog shelter in the country."

The altruism, though, kicked into high gear when Simon was diagnosed with colon cancer in 2012. "The truth is, I have more money than I'm interested in spending," he told THR in July 2013. "Everyone in my family is taken care of. And I enjoy this." (Simon was twice divorced, from actress Jennifer Tilly and Playboy Playmate Jami Ferrell, and had no children.) After an emergency operation for sepsis, when he came close to dying, he made plans for after he was gone with the help of Manhattan-based Rockefeller Philanthropy Advisors. "When I woke up in the hospital, even though I did have a will, it did become that much more important to me to set this up for the future," he said. Of his philanthropy, he promised THR, "it's something that will be living after I'm gone."

Simon simply may not have discussed his intentions for financial support for Columbo's care or for ongoing support of nonprofits with his advisers; in the medical marijuana-fueled haze of his decline, he didn't make any plans for his funeral either, forcing Tilly, who declined to comment for this story, to step in immediately after his death and help arrange for a suitably elaborate sendoff, a service that included eulogies by Simpsons showrunner Al Jean and PETA president Ingrid Newkirk (flowers on the casket were arrayed in the form of Bart Simpson, with an air bubble reading, "Later, Man"). Still, a question remains whether Miller and Simon's estate planner, Bradford Cohen, a well-regarded entertainment industry tax lawyer at Venable in Century City, brought these pet-care expenses up with him while he was alive.

Bradford Cohen, an entertainment industry tax lawyer, helped establish Simon's estate plan.

"It's best practices," says Beverly Hills-based estate planner Ryan J. Shumacher of Rosenfeld Meyer & Susman. "You ask them if they have pets and then, if so, if they want money attached to the pets. People don't necessarily know to bring it up." Adds another planner, Stefanie J. Lipson of Century City's Greenberg Glusker: "Unless the person receiving the pet is clearly beyond the means of needing financial assistance, the client makes an offsetting provision of care."

Irene Dayag, Simon's home nurse, who attended to his daily needs for his final two years, accompanying him everywhere from business appointments to the toilet when nausea struck, firmly maintains that, whatever the decision-making tree, the alleged result appears "out of character" for the patient she so intimately knew. "It's clear to me Julie has no idea who he was and what he wanted."

•••

The tattooed Tyson, a former model for the likes of Jean Paul Gaultier and Dolce & Gabbana, has been training dogs for two decades. Unlike Cesar Millan, whose M.O. is to place troubled dogs with a group of other canines to socialize them, he tailors his approach to "an urban, domesticated space and learning how to assimilate into our human world, where there are our rules, not the natural rules of the pack." He's known for strictness — even A-list owners are told to scram if they don't follow his edicts. "When Tyson says that you have to show up for your dog, he doesn't care who you are," says Alison, 51. "Your dog doesn't know you're a celebrity."

By Tyson's telling, Simon called on him for help after he realized he couldn't stop a young Columbo from attacking people who ventured onto his property. "It was anybody — housekeepers, gardeners, pool cleaners, construction workers remodeling Sam's house, the UPS guy," says Tyson. "Sam's place was always a very dynamic environment, full of some really gregarious characters. [Simon's friend] Howard Stern, this 6-foot-5 guy with big hair, would just set [Columbo] off."

Tyson initially was reluctant to work with Columbo, concerned that one of the world's leading animal activists wouldn't be on board with his use of physical corrections in training. But Simon quickly disabused him of the notion. "He said, 'Tyson, I already have him on a pinch collar, so don't worry about that. Just get your ass over to my house and save this damn dog's life,' " Tyson recalls.

Simon funded a 184-foot anti-poaching ship for the Sea Shepherd Conservation Society, which named it in his honor.

Immediately upon meeting Columbo, Tyson says he could tell that "on a difficulty level of one to 10, this would be a 12," and what followed turned into a commitment in which "I was out there at his house five to seven days a week for a couple of hours at a time for several years."

Along the way, with so much time spent at Simon's place, a bromance ensued over cigars lit while watching football games and old fight tapes, bringing Tyson into the star's innermost circle. "Sam thought a lot of Tyson," says network comedy veteran Merrill Markoe (she developed "Stupid Pet Tricks" at Late Night With David Letterman), a close friend of Simon's since the 1980s. "He was there at the house constantly." A Vanity Fair profile published five months before Simon died begins with Tyson accompanying Simon, Tilly and Pamela Anderson on a rented Gulfstream IV to Denver to visit an animal sanctuary housing half a dozen bear cubs Simon had saved from a roadside bear-pit attraction in rural Georgia.

Tyson and Simon had a budding creative partnership — at the time of Simon's diagnosis in 2012, they had cut a sizzle reel for a reality show called, natch, Death Row Dogs, and were taking meetings with Mark Burnett. Tyson first took note of Simon's depleted stamina when, stepping out of the producer's Santa Monica office late one morning, Simon shrugged off their customary post-Burnett lunch at the nearby Ivy at the Shore: "It was just the way he said, 'I'm not feeling well today.' "

Soon after, the Kilmers say Simon's assistant, Michele Wytko, told Tyson he'd been admitted to the hospital. (Wytko declined comment.) "I rushed there," says Tyson, "and Sam begged me to take Columbo. He was like, 'Tyson, will you please take him? I'm dying.' " Alison continues: "Sam said he was taking care of everything, so we assumed that meant everything. We never asked for him to sign some piece of paper proving it." (Simon would go on to live a few more years.)

Adds Tyson, "I didn't volunteer. I only accepted because of the situation, and I wouldn't have agreed to handle this animal without having a [financial] structure in place. This is a Cane Corso, and I have two children."

•••

The grief transition for Columbo, already a fragile dog, has been tough — exacerbated by the loss of his alpha-female partner Gerti, an Irish wolfhound with hip and back trouble but no aggression issues, shortly before Sam died. (Alison: "She was very much the matriarch, bossing him around, and he was fine with that.") To help cope, Tyson — who arranged to be present at the moment of Simon's passing at home and imme­diately secured Columbo in time for the coroner and sheriff's deputies to arrive — took some of Simon's dirty clothes to his own house. Later, he brought Columbo back to the Pacific Palisades property as part of the detachment process. The dog lit up, running around and up onto Simon's bed, where he used to sleep up against Simon while he was sick.

After Simon's death, the Kilmers claim Miller quickly disabused them of the notion of forthcoming funds after they reached out. "We got on the phone and she said, 'Well, Tyson, I'm just here to tell you that there's nothing for Columbo and it's really too bad and I'm sorry but my hands are tied,' " says Tyson. "I said, 'Julie, this dog needs treatment.' And then she goes, 'I'm well aware of what he needs. I've been paying those bills for years.' "

Up for sale at a Sotheby's auction on Nov. 18, Thomas Hart Benton's 'T.P. and Jake' (estimated sale price $1.5 million to $2.5 million).

Nevertheless, they allege that after some consideration, Miller said she'd look into financial assistance, asking for an itemized cost estimate if Columbo lived to be 12, which the Kilmers provided and based on Simon-era numbers (the trust doesn't dispute this). The numbers are beyond most people's imagination: Tyson's own aggression training at $7,500 per month, the aforementioned twice-a-week acupuncture at $3,640 per month, grooming at $150 every three weeks, supplements at $185 every three months and gluten-free, regionally sourced food at $180 per month. This amount came to roughly $138,000 per year. It didn't include their request for $25,000 to build out a "super-basic" backyard enclosure like the one Simon had constructed at his place for Columbo. (The trust, in its statement to THR, positioned the $1.7 million total as a "request" and "ludicrous" but would not comment on whether the monthly expenses were identical to those spent when Simon was alive.)

According to Tyson, "Julie said, 'Oh, that's over-the-top, there's no kind of money like that, and we're not obligated to give you anything.' And I was like, 'Then why did you ask us to mock up this estimate when you knew how much this costs?' And [Julie] said of the enclosure, 'Well, that's extravagant.' It's extravagant for the man-eating dangerous dog? To say this dog doesn't need an enclosure is to say a panther doesn't need an enclosure."

Trainer Victoria Stilwell of Animal Planet's It's Me or the Dog notes that while "$9,000 per month may sound quite steep, it's not far-fetched for this kind of very troubled animal, with these sorts of challenging issues where there's no cure, only managing and coping. This is just what this costs for constant vigilance — otherwise, without a doubt, dogs like this end up at the pound."

Simon and his then-wife Tilly during the 1988 ACE Awards at the Wiltern Theater in Los Angeles.

As the negotiations continued, the Kilmers offered to cut the fee for training and boarding in half. Still, many might wonder why Tyson wouldn't waive his substantial monthly training fee since Columbo, after all, had become his dog. It's a contention that's met with a heated response, laying bare the boundary of the responsibility he feels he has taken on. "I'm a paid professional to do this work," he says, noting that he didn't volunteer to displace or lose his income. "When I'm doing this [training] for Columbo, I'm not doing this for other people's dogs."

After several months of negotiation, Miller offered a one-year financial commitment and mandated that costs come down by finding a less expensive vet and ending Columbo's acupuncture therapy.

The Kilmers say that, despite the clashes, the estate had paid Columbo's expenses through June, when they requested a copy of the trust in an attempt to see what Columbo was entitled to receive. "When we said we wanted to see the trust document, she said that Sam was really private and, besides, it's unimportant because there's nothing in it for us. So we hired a lawyer."

The interior of Simon's Pacific Palisades home; key furnishings and artwork also are on the block in auctions this fall.

"Usually the beneficiary is entitled to see the trust document," says Southwestern Law School professor Michael Berger. But the Kilmers' attorney only was able to extract a brief, redacted portion. (The Kilmers did not share those documents with THR, saying they are prohibited from doing so.) And once they took a legal step, the estate stopped Columbo's funding. Since that time, the Kilmers say they have spent $19,500 paying staff for time dedicated to Columbo's care and have other vendors complaining that the trust has paid them late. They are now considering a GoFundMe campaign to pay for the dog's mounting costs.

•••

Simon and fellow animal-rights activist Anderson spoke to the media in December 2013 to protest the annual commercial seal hunt in Newfoundland and Labrador.

The custodians of Simon's of public-facing animal altruism have found themselves in a similar quandary. His key charities — PETA, Sea Shepherd and the L.A.-based Mercy for Animals — say they haven't received support since his passing, and since his funding had been so generous, the effects already are being felt.

Mercy for Animals declined to comment on the issue. PETA, in a careful statement, wrote, "Sam always promised that, after his death, PETA would be looked after in a very significant way." Noting that "his estate is complex and we can only imagine that it requires an enormous amount of work and time to sort out," the nonprofit concludes, "without his presence, we miss being able to do some of the extraordinary things his generosity and kindness enabled us to do when he was alive," including buying animals from roadside zoos.

The more politically radical Sea Shepherd is far less diplomatic. Its leadership forcefully argues that Simon had made it clear to their organization that his eponymous ship's continued maintenance, operation and even replacement would be backed by the estate in the form of a bequest. Says Watson: "Sam would not have turned his back on his ship."

The trust promises that Simon's eponymous charitable-giving foundation, activated after his death, will eventually "direct a substantial amount to organizations that protect and save animals from cruelty and mistreatment, along with other causes." For now, Miller "is still sorting things out, as required by her legal and ethical obligations," says Hiltzik. Estate planning experts say that it's not uncommon for trustees to leave charitable donations to the end of a lengthy unwinding-of-finances process during which they prioritize the IRS and creditors. (The federal estate tax return, for instance, is due nine months after the date of death — in Simon's case, Dec. 8.) Still, those same experts agree that with an estate as large as Simon's, trustees typically would exercise discretion to bridge key extant altruistic commitments in the interim if they wished. "They do have the executive power," says Berger. Not that it much matters. After all, explains USC law pro­fessor Edward J. McCaffery, another estate plan­ning specialist, "charities are reluctant to sue in any case because they don't want to scare off donors or spend the money on attorneys."

Regardless, Simon's oldest friends contend he'd be astonished by what's gone on since his death. "I know that he was completely committed to those charities, talked about them to me frequently and can't imagine that he wouldn't want his support to be ongoing," says TV writer Heide Perlman (Cheers, Frasier), who knew him for more than three decades. Adds Markoe of Columbo's care: "Sam would be humiliated and enraged," going on to say that "at the very least, Sam would have expected Columbo's care to be the same as it was when he was alive. He was thrilled when Tyson said he would take Columbo — thrilled and relieved. He would never have agreed to cut off funds for his own f—ing dog!"

In life, Simon's desire was clear: "I just wanted to have some days where I get to see animals walk in grass for the first time," he told THR in 2013 while getting by on Ativan, used to treat depression, anxiety and insomnia. In death, his voice is harder to hear, complicating or at least delaying what he expected to be a proud legacy.

For now, Miller is busy overseeing the sale of the Pacific Palisades property, listed for $18 million (the two-home parcel includes Richard Neutra's 1948 Bailey House, part of the vaunted Case Study program), and off-loading much of his art collection and Simpsons memorabilia in a series of Sotheby's auctions beginning Oct. 2. That includes a famous Thomas Hart Benton painting of his 11-year-old son T.P. and dog Jake from 1938, which serves as the emblem for Simon's foundation and has an estimated sale value of $1.5 million to $2.5 million. In 1946, Benton penned an obituary for the dog in The Kansas City Times. "No one who saw the meeting of the boy and dog could ever forget it," he wrote. "They forgot their own emotions in this more intense one of a devoted animal. His yaps of joy sailed up ... and came back to pierce your heart."

Back in Encino, the Kilmers are facing down what comes after the parting of the dying man and his aging best friend. "I'm committed to this dog; Sam would be pissed at me if I didn't fight for him," says Tyson, his voice weary, reaching out to stroke Columbo's back. "But the older he will get, the harder his joints will hurt him, the grumpier he'll be." He looks down at Columbo, curled in repose once again, with love and dread: "This is a forever deal."