VIDEO: Conan O’Brien Back At Work After Scary Fall

Funnyman Conan O’Brien was back to work on The Tonight Show Monday night –joking about a scary fall during a taping of his show last Friday that literally knocked the air out of him.

O'Brien laughed about the accident Monday and even showed video of his wipe-out on the hard studio floor.

"As many of you may know, on this past Friday's show I was doing a stunt and I hit my head and suffered a slight concussion. And I promise, if you're a good audience, I'll do it again tonight," O'Brien said during Monday's taping.

At one point, O’Brien quipped that he struck his head so hard "that for five seconds I actually understood the plot of Lost.

O'Brien and guest Teri Hatcher were in a footrace when he wiped-out while trying to slide past the finish line, forcing Friday's show to be stopped mid-taping.

"I knew you'd hit your head. It looked like it was serious but then you called for a slo-mo," or slow motion replay, said his announcer, Andy Richter.

O’Brien said he didn't remember clearly what happened next, as he went to his dressing room to change into a suit for the next segment, an interview with Family Guy's Seth MacFarlane.

But back on stage he looked down at his blue cue cards and realized he didn't know what to do.

"It was like a menu for an Egyptian restaurant," O'Brien said.

His producer called him off the stage. O'Brien kept wanted to keeping taping the show, while his staff and a nurse asked  him  what year it was, Richter said.

Richter accompanied him to the hospital, where doctors did a neurological evaluation.

"I really start to come back and I feel much better. And then one of the neurological questions was how many nickles in $1.35?" O'Brien said. "I've never known that!"

A Tonight Show rerun aired Friday instead of the fresh episode.