The new season of HBO's True Detective premieres this weekend, and to get everyone in the mood Jimmy Fallon brought out stars Colin Farrell and Vince Vaughn  to play a new Tonight Show game called True Confessions on Thursday.

Set in a dark room at an interrogation table complete with an ashtray, fake cigarette smoke, and paper coffee cups, each player picked one of two envelopes in front of them and read the admission inside—one was something that actually happened to them and the other was a lie. It was up to the other two players to figure out the truth.

Farrell went first with this creepy disclosure: “When I was a late teen I got brought in as a suspect in an attempted murder.” Fallon and Vaughn immediately began to lob hardball questions at him until Vaughn stopped and said, “I’m a little nervous to push too hard because we might have a guy who got away with murderer here. I want to play a fun game!”

Fallon agreed, adding, “I’ve got a feeling this really happened to him and I’m afraid.” With good reason—Farrell was telling the truth! “I saw a [police sketch] of the guy who actually did the crime" he said. "And it looked remarkably like me.”

Next up was Fallon, and his was a no-brainer as the truth: “I got my head stuck in a fence and my grandma used mayonnaise to squeeze me out.” Click the video above to find out if Vince Vaughn did or did not once don a bald cap and star in the title role of The King and I.