Ben Affleck says he suffered many, many bad hair days for the sake of his art in Argo.

The actor, 40, rocked a distinctive shag and beard for the film, based on the true story of six Americans held captive in Iran amidst its revolution in the 1970s. "I hated it!" Affleck admitted at a Saturday press conference at the Toronto Film Festival for the movie. "I had to grow out this Davy Jones/Barry Gibb thing I had on my head. I knew I was doing the movie far enough in advance that I knew I could grow it out."

PHOTOS: Ben and Jen's love story

Indeed, the entire cast of the film committed themselves to looking 70s-authentic. "Everybody went for it. There was no vanity among the actors."

The father of three and husband to Jennifer Garner continued: "[My costars] might have been, 'No, I gotta look good in the movie.' It was all 'how much can I look like the real people'?"

Sitting directly to his right in the panel, Affleck's costar Alan Arkin then interjected with a bizarre tangent involving Tom Cruise.

PHOTOS: Ben's J-Lo days

"Does anybody do that? Besides, maybe, Mr. Cruise?" Arkin, 78, asked. As the crowd laughed awkwardly, Affleck looked bewildered at the mention of the Oblivion star, 50.

"I hardly run ever across anybody . . . " Arkin went on.

"Anybody who in Hollywood who is vain?" Affleck said, finishing Arkin's thought.

PHOTOS: Jennifer Garner's third pregnancy with son Samuel

"People that I've worked with. It's part of our work. Unless you're a major star and have this image," Arkin explained, seemingly referring to Cruise, 50 -- who in fact transformed into a late-middled aged, overweight man in Tropic of Thunder. "I don't know a working actor in a period piece who wouldn't. It's part of our job. I'm sorry... did I speak out of turn? I've cast a terrible pall!"

Argo hits theaters Oct. 12.

This article originally appeared on Ben Affleck: "I Hated" My 70s Hair, Beard in Argo