AceShowbiz - Actor Paul Bettany's father was forced to conceal his sexuality at the age of 83 after his lover of 20 years passed away.

The "Avengers: Endgame" star reveals his dad Thane Bettany, who was a strict Catholic, feared for his "place in heaven" and insisted his homosexuality was "a big misunderstanding."

The 49-year-old admits his new film "Uncle Frank", in which he plays a closeted gay professor dating a Saudi Arabian immigrant, brought his father's plight home to him.

"I had a gay father who died a couple of years ago," Bettany tells Total Film. "He came out of the closet at 63. He then had a 20-year relationship with a man called Andy Clark. It was a joyous relief for everybody, actually."

But after Andy died, Bettany's dad went back into the closet.

"Once his partner died, he was in his 80s at that point, my dad decided to go back inside the closet and say that it had all been a big misunderstanding because he was a Catholic and concerned about getting past Peter through the pearly gates," Paul explains.

And the U.K. native can't imagine the grief his late dad experienced.

"The shame he felt for his sexual identity was devastating," he adds. "He was unable to mourn the person who I think was the love of his life."

Thane, an actor, dancer and teacher, hooked up with his lover, Andy, after his divorce from Bettany's theatre teacher mother.

"Uncle Frank" director Alan Ball also shared that he had similar experience, saying that he believed that his dad might have been gay and that bonded him with Paul. "We talked about it a lot, and the fact we both had very traumatic experiences in our adolescence and how those stayed with us," he said. "For Paul, the movie became a chance for him to have his own 'what if' story about his father. What if he was able to really embrace who he was and live his life fully?"