By Christian Holub
Updated February 03, 2016 at 01:26 PM EST

It’s a time of looking back for David Schwimmer right now. Not only is the former Friends actor currently starring as Robert Kardashian on American Crime Story, he also stopped by The Late Show on Tuesday night for a reunion with an old college buddy. Schwimmer and Stephen Colbert not only studied theater at Northwestern University together, they were even in the same improv group. Colbert produced a photo to prove it, complete with hilarious throwback hairstyles. Ever the nerd, Colbert didn’t miss the opportunity for a Star Wars reference.

“You have hair that Kylo Ren would love,” Colbert said, referencing Adam Driver’s character in The Force Awakens.

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Schwimmer explained that doing improv with a young Colbert is actually what inspired him to go into more traditional acting.

“I could never keep up. Your mind is just so ridiculously fast,” Schwimmer said. “I actually was very grateful for being in that group with you, because I realized, ‘Oh, that’s why I can’t do that. I should go into acting, and not that.’ “

College friendships are an important factor in Schwimmer’s current role. As he explained to Colbert, Kardashian’s friendship with O.J. Simpson dated back to their time at USC.

“It was USC football, actually. They knew each other for almost 25 years before the trial,” Schwimmer said. “They were very good friends, best men at each other’s weddings, the families would vacation together. They went into business with each other.”

Watch the full clip below.