With Fast X, Alan Ritchson joined the elite group of actors who’ve been invited into the ensemble for one of the biggest action franchises ever, but that doesn’t mean he was a major fan going in.

In an interview on The Rich Eisen Show last week, Ritchson — who made the leap to Fast X on the heels of the success of his Jack Reacher streaming series — revealed to Eisen that, apart from seeing the first Fast and the Furious film when he was “in high school,” he hadn’t actually been keeping up with the series in the 20 years since when he was given a shot at a role in Fast X.

That’s a fine thing to admit now, particularly since Ritchson clarified that once he was cast he went back and watched every film in the franchise, but he also admitted to Eisen that he revealed this information to franchise star Vin Diesel, and was “mortified” to hear the words coming out of his mouth.

“I didn’t watch any other ones, and I let Vin know,” Ritchson said. “I go ‘Hey man, I hadn’t really watched any of ’em. I watched the first one in high school, and now that I got the part I’ve seen them all, and I just love what you’ve been doing with the last two decades.’ And he was like ‘I…thank you. I appreciate that.'”

When Eisen asked how Diesel really reacted to the news, Ritchson suggested that the Fast Saga star was “very polite,” but could only imagine what was really going on in his head.

“He’s spent 20-plus years of his life, this is his baby,” Ritchson said. “I’ve spent a couple years working on Reacher. It’s such a fixture in my life, if somebody was like ‘Thanks for having me on Reacher, man, I haven’t watched any of ’em,’ I’d be like ‘You’re the stupidest…why would you say that?!’ And this dude is decades in. I’m an idiot.”

Ritchson’s story is far removed from that of his fellow Fast X star Brie Larson, who’s explained throughout the film’s press tour that she’s a lifelong fan of the franchise and found herself geeking out on the film’s set when she got to share scenes with Diesel. Still, he made it clear that now that he’s a part of the story, he’s watched every film, and become a fan along the way.

“The more I saw it develop, the more I was like ‘Oh no wonder this is a multi-billion dollar franchise, this is the funnest thing in the world,'” he said.