The star of The Cat That Changed America has much in common with the other A-listers in his adopted city of Los Angeles: the camera loves him, he has fans all over the world and he has mastered the trick of seeming relatable, despite hiding from the public in the Hollywood Hills.

In other respects, though, the mountain lion known as P-22 is an unlikely celebrity. The film, which had its LA premiere this week, tells the story of how it happened. At first P-22 was thought to be no more than an urban myth. Few people believed the scattered reports that a puma was roaming Griffith Park, the island of city-centre wilderness where the Hollywood sign stands. Then in 2012 a biologist captured images of the beast, 6ft 6in long, on a wildlife camera. The following year National Geographic filmed P-22 roaming his territory at night.

He has since been fitted with a GPS collar, which enables scientists to track his movements around the park and occasional sorties into nearby residential areas. Mostly he hunts wildlife on the hills and trekking trails but he is particularly partial to the deer in Forest Lawn cemetery, where Buster Keaton, Stan Laurel and Carrie Fisher, among others, are buried.

Last year he became the chief suspect when a koala vanished from Los Angeles zoo on a night when surveillance video and GPS data put him at the scene of the crime, but the city rallied behind him and he was allowed to stay.

Beth Pratt-Bergstrom, California director of the National Wildlife Federation, says that Angelenos see themselves in P-22’s story. He is a migrant in a city of migrants who wandered from the Santa Monica mountains to the park, crossing two busy freeways in the process, only to find himself stranded and cut off from potential mates. “Who can’t relate to being dateless and stuck by traffic?” she says.

Tony Lee, director of the documentary, was beguiled by the romance of P-22’s story. “He’s the poster cat for urban survival.” P-22 now has his own Facebook, Twitter, Instagram and Tinder accounts — all maintained by Ms Pratt-Bergstrom, who has become so absorbed in the cause that “my husband feels like I’m having an affair”. She carries a giant cardboard cutout of the cat in her car and has a tattoo of his face on her left upper arm. In the film she compares P-22’s pioneer spirit to Neil Armstrong stepping on to the moon. She is trying to raise $50 million for a wildlife bridge across the 101 freeway. She is $47 million short, but optimistic.