EXCLUSIVE: The Sad Secrets of 'Monty Python' Comedy Legend Terry Jones' Brutal Final Days Laid Bare — As His Wit, Charm and Intelligence Were Devoured by Same Form of Dementia Killing Bruce Willis

Terry Jones spent his final years trapped in a worsening silence as the same rare dementia now afflicting Bruce Willis steadily stripped away the comic force that helped reshape British humor, RadarOnline.com can reveal.

The comedy trailblazer's sad end is detailed in a new authorized biography that tackles the Monty Python star's decline.

Seriously Silly, written by Robert Ross, brings together decades of interviews and personal accounts to chart the life of Jones, from his rise as a writer, director, and performer to the eroding final chapter defined by primary progressive aphasia, the frontotemporal dementia that destroyed his ability to speak and socialize before his death aged 77.

Die Hard actor Willis, 70, is suffering from the same disease, which his family disclosed in February 2023 after a period of cognitive decline and withdrawal from acting.

Ross also sets out the broad arc of Jones' life – how he was born in 1942, rose to prominence with Michael Palin and the Monty Python troupe from 1969 onward, and later moved to Highgate in north London with his partner Anna Soderstrom, where he spent his last 15 years.

It also reveals trivia such as how Jones wrote a script for Gremlins II that was rejected by Steven Spielberg.

But the book's most striking material centers on how the illness hollowed out Jones' once-sparkling and razor-sharp personality. It reveals he continued to host the elaborate dinner parties he once loved despite barely speaking towards the end.

His daughter Sally Jones tells Ross about the bashes: "He just started talking less and less." Although her iconic father remained sociable, he ultimately increasingly retreated inward, even as he persisted with long walks on Hampstead Heath.

Ross reports Jones' speech troubles began in the years after his marriage to Alison Telfer ended, and he became a father again at 67. Friends noticed he struggled to recall lines during the 2014 Monty Python reunion shows, prompting concerns for his health.

Palin, who had worked with him since their Oxford days, said: "Frontotemporal dementia may cause loss of inhibition, but Terry was never very inhibited in the first place." He added the change in his comedy partner was nonetheless unmistakable.

Those close to Jones describe a pattern of erratic behavior as the disease ate him alive. One family source told RadarOnline.com, "Terry could seem fine one moment, then fire off a baffling email in the middle of the night the next. "But you could see it wasn't malice – it was the illness tightening its grip."

Another long-time friend said: "Terry was still the host, still the showman, but the words were slipping away from him. People would leave those dinners shocked by how quickly he was fading."

Ross also sets Jones' experience in the broader context of frontotemporal dementia, the same condition that has sidelined Willis from acting.

Willis' family said the former movie hardman had faced increasing language impairment, confusion, and difficulty communicating before he was forced to step away from acting – symptoms mirroring the trajectory charted in Jones' painful final years.

Jones' decline was marked by a narrowing world, with him retreating into repeated viewings of his comfort movie, Guys and Dolls, as well as taking familiar walks on familiar paths near his home.

Director Terry Gilliam recalled seeing his old colleague on Hampstead Heath in those years.

"He was dressed immaculately," he said. "But there was no one at home. He was a shell. A beautiful shell."