The Insider.com

Things got a little heated when James Van Der Beek showed up on Conan Thursday night.

• September 14, 2012'Good Wife' Brings Back A Fan Favorite
• September 13, 2012Our Favorite 'SNL' Celebrity Impressions
• September 13, 2012Exclusive Preview: 'Secret Princes'
• September 13, 2012Elizabeth Mitchell Previews 'Revolution'
• September 13, 2012'Heathers' TV Remake: Dream Casting
• September 13, 2012Beyond Bluths, Who's Getting 'Arrested' Again?

While yucking it up with host Conan O'Brien, 49, the Don’t Trust the B—– in Apt. 23 star, 35, was interrupted by sounds of an alarm (about 3:15 minutes into video). "Is that a fire drill?" Van Der Beek asked.

"So let me get this straight, James Van Der Beek," Conan joked with the actor as the alarm got louder. "You wait 14 years, 14 years, 'til it's safe to come back on this show and there's a f–in' fire alarm!"

Van Der Beek had not been on a late-night show with O'Brien since his days on Dawson's Creek. Without missing a beat, the host didn't pass up a chance to make light of the situation, joking, "Let's go to commercial and figure out what we're gonna do, cause the fire department loves when I get to the plug before we evacuate people."

Even when he moves to TBS, O'Brien is still having to put out fires.