William Hasley, a 78-year-old Hollywood screenwriter and UCLA instructor who ghostwrote Caitlyn Jenner's 1996 self-help book, collapsed and died on a hiking trail at Los Angeles's Runyon Canyon on Saturday evening. Rescuers reached him off Nichols Canyon Road near Hollywood Boulevard, but he was declared dead shortly after.
The Los Angeles County Medical Examiner's Office has not released a cause of death, saying additional investigation is pending. No one has publicly explained what triggered the collapse, and it remains unclear whether Hasley was hiking alone.
Hasley's death marks the second loss in Jenner's close circle in less than a year, following the July 2025 death of Sophia Hutchins, Jenner's 29-year-old confidante and manager, who fell 350 feet from a cliff near Jenner's Malibu home.
The New York Post reported that Hasley was found at approximately 7:05 p.m. Saturday. The LAFD responded with its Air Operations unit.
An LAFD spokesman described the response:
"LAFD Air Operations lowered rescuers to the patient, and medical treatment was administered."
Despite those efforts, Hasley was pronounced dead at the scene. The Daily Mail reported the discovery time as 6:42 p.m., a slight discrepancy with the Post's account. Either way, the timeline points to a late-afternoon or early-evening collapse on one of Los Angeles's most popular urban trails.
A source told the Daily Mail that Hasley had been on the UCLA campus just the day before and showed no signs of trouble:
"Various people spoke to him on Friday and he didn't have any health issues."
A neighbor offered a more somber reflection to the Post: "It's very sad he had to die all alone like that."
Hasley built a long career in the entertainment industry. He worked as a screenwriter with Universal Pictures, Warner Brothers, and 20th Century Fox. At the time of his death, he was still teaching, serving as an instructor in screenwriting at UCLA.
His UCLA biography painted a picture of a man who stayed busy well past the age most people retire. It noted that when Hasley wasn't meeting a deadline, he could be found "fighting City Hall over an environmental issue, writing an article, teaching a writing class at UCLA, volunteering in a soup kitchen, or speaking to a youth organization." The bio also described him as a sports enthusiast who played in celebrity golf tournaments and a Showbiz Softball League.
In the entertainment world, sudden deaths of prominent creative figures have drawn public attention with increasing frequency in recent months.
Hasley was briefly married to actress Robin Riker, known for the show "Brothers," in 1987. His most prominent published work was Jenner's 1996 book Finding the Champion Within, released through Simon & Schuster. The book examined Jenner's life as an Olympic gold medalist.
Hasley's death comes after Jenner already endured a devastating loss. In July 2025, Sophia Hutchins, who had served as Jenner's manager and lived in Jenner's home since 2017, died after plunging 350 feet down a cliff near Jenner's Malibu residence. Hutchins was 29.
Hutchins had been part of Jenner's inner circle for over a decade after Jenner came out as a transgender woman in 2015. She cited Jenner as the inspiration for coming out in college in 2016 and moved into Jenner's home the following year. Hutchins took over the manager role previously held by Kris Jenner, Caitlyn's ex-wife, after their 2015 divorce.
Hutchins appeared in multiple episodes of I Am Cait and told The New York Times that she and Jenner "were never romantically involved."
Two people close to Jenner dying in unusual outdoor circumstances within roughly a year is a grim coincidence. Hutchins fell from a cliff. Hasley collapsed on a trail. Neither death has been fully explained by authorities.
Cases involving people found dead in outdoor settings often leave families waiting weeks or months for answers from medical examiners.
The Medical Examiner's Office has offered no timeline for releasing Hasley's cause of death. The Daily Mail said it contacted representatives for both Jenner and UCLA but had not received responses.
Several basic facts remain unknown. Was Hasley hiking alone or with companions? Did he have an underlying medical condition? What exactly caused him to collapse? The Friday campus sighting suggests he was active and apparently healthy just hours before his death.
Runyon Canyon draws thousands of hikers each week, from tourists to longtime Angelenos. The trail's steep terrain and summer heat have contributed to medical emergencies before, though the specific conditions at the time of Hasley's collapse have not been detailed.
The entertainment industry has seen a string of unexpected deaths in recent months, each leaving its own set of unanswered questions for families and investigators.
Hasley's passing also underscores the risks that come with strenuous outdoor activity for older adults, even those who appear fit and active. A man who played in softball leagues, rode horses, and hiked LA's canyons at 78 was hardly sedentary. But trails don't care about your résumé.
Investigations into sudden deaths in public settings often move slowly, and the families left behind are the ones who pay the price of that wait.
For now, a man who spent decades writing other people's stories, including the story of one of America's most famous athletes, has no one left to write the final chapter of his own. The Medical Examiner's Office owes his family, and the public, a timely answer.
