The origin of one of Hollywood’s most iconic stars is a story stranger than fiction.

Cary Grant, who appeared in movies including “To Catch a Thief” opposite Grace Kelly, was born Archibald Leach in 1904 to an abusive father in the sleepy city of Bristol, England. While he was a child, Grant’s mother was secretly committed to a mental health hospital and publicly declared dead. The actor only found out she was still alive when he was 31 years old.

Grant is now the subject of “Archie,” a four-part biopic from “Philomena” writer Jeff Pope, made with the cooperation of his ex-wife Dyan Cannon and daughter Jennifer Grant. The series charts the actor’s rise to fame, his struggle with his demons and his relationships with the most important women in his life.

“It was Dyan who told me in much greater detail than you can find anywhere about the whole thing with his mother,” Pope said during a press screening of the series in London earlier this month. “And I just couldn’t get it out of my head. I thought what an incredible story to be told. It made me think of Dickens and ‘Great Expectations.’”

The result is a tale of two timelines and, in some respects, two protagonists: young wannabe actor Archie Leach, played by Calam Lynch (“Dunkirk), and middle-aged superstar Cary Grant who is portrayed by Jason Isaacs (best known as the oleaginous Lucius Malfoy in the “Harry Potter” franchise.)

Having swapped Malfoy’s long blonde wig for brown contact lenses and a prosthetic chin dimple, Isaacs bears more than a passing likeness to the actor. But when he was first approached for the role “I thought it was a fucking terrible idea,” he said during the press screening. It was only because Pope wrote the script that Isaacs agreed to read it. When he did, he quickly realized the series wasn’t about Cary Grant at all but Archie Leach, the man masquerading as him.

“Cary Grant didn’t exist,” Isaacs said. “Cary Grant was someone that a man invented because he was so tortured. And I thought, ‘I can play a really messed up man who can fake many things in many situations to many people.’ I can’t play Cary Grant, but I can have a crack at playing Archie Leach.”

The real Grant was not the man film fans had come to know. Intensely private, he rarely did press, and it was only after Isaacs tracked down a rare interview Grant had done with a student radio station in the last years of his life that it emerged his real off-screen accent still held a distinct trace of Bristolian English. On celluloid, it had been masked by the traditional mid-Atlantic twang. “If people want to see Cary Grant, they can watch his films, they’re amazing,” Isaacs said. “But this is what happens when he steps off set.”

Left-right: Jason Isaacs as Cary Grant in “Archie,” Cary Grant in 1946 film “Notorious”

The project was originally envisaged as a feature film, but Pope quickly realized he wouldn’t be able to properly capture Grant’s “essence” in 90 minutes. “He was a desperately troubled and unhappy, haunted human being who had a terrible, abusive childhood,” Isaacs said of his character. “Which was one of the things that the screen can never got across: He was hungry, he was starving. And he was starved of love.”

What saved him, Pope shows, was his relationship with Cannon, a fellow actor, and, even more crucially, having daughter Jennifer. He met Cannon, 33 years his junior, while on the rebound from Sophia Loren. At the London screening, Cannon, now 86, acknowledged that theirs was a significant age gap. “He was older than my father,” she said. “Many women have this thing that we want to please — we want to serve, and when that’s taken advantage of, you become not yourself anymore. You lose yourself; like, completely, I was gone.”

The relationship, which Cannon said became increasingly controlling, didn’t last, but it did produce Jennifer, who transformed Grant’s life. He was 62 when she was born and, for Pope, their relationship was one of the many intriguing things about Grant’s inner life. At the height of his fame, he effectively gave up his career to become a stay-at-home father — and a great one to boot, Jennifer has said. It’s a trait Isaacs instinctively understood. “He was more comfortable with kids, frankly, than with adults,” said the “Harry Potter” actor. “Certainly I always have been [too].”

While Cannon and Jennifer ’s input was integral to the production, Pope was clear that “Archie” is not a hagiography. “In the end, it has to be my take on everything,” said the showrunner. “It’s not the officially approved Grant family version. There is editorial independence.”

Cannon, who has become the de facto keeper of Grant’s legacy, is open about the fact that her ex-husband was not an easy character to live with — or portray on screen. She described the man behind the legend as “complicated, funny, sardonic, controlling, imaginative, kind, commanding — so many things. That’s what interested me.”

Oh, and a “Great lover,” she purred. “A great lover.”

“Archie” drops in the U.K. on ITVX on Nov. 23 while U.S. audiences can catch the series on streamer Britbox from Dec. 7.