From child star to superstar. Ben Affleck appeared on a 1984 PBS series when he was a kid, he revealed during an interview with Jimmy Fallon on Thursday, October 6.

When Fallon, 42, first made mention of the 44-year-old actor’s kid acting past, The Accountant star was quick to clarify that he really only had one gig as a young, aspiring actor.

“I was, I did do some child acting, [but] I wasn’t the child actor who — luckily I didn’t end up on a show and get famous and go on crack and go crazy,” Affleck said with a laugh. “I had a normal childhood, and then my mother let me do this thing and then forced me to come home.”

The show, a short-lived 13-episode series called The Voyage of the Mimi, featured several children “combining science and math topics with some interesting adventures” alongside a scientist, Affleck explained.

In a short clip that Fallon then unveiled, a young Affleck looks serious as he discusses the idea of whales’ ancestors living on land. “Well, you know, I kind of found that hard to believe,” Affleck says onscreen. “I wanted evidence, and I figured if I could find it anywhere, it would be at the natural history section of the Smithsonian.”

The Batman actor laughed at his young self and joked to Fallon afterward, “That was before I had testicles.”

“I used to wonder why — I’d get mad at the operator, like, ‘I’m not a woman!’” he said. Watch the hilarious clip above to see the Hollywood star in his acting debut.

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