letterman colbert crossover Stephen Colbert drops by David Letterman's show ... to use the bathroomCrossovers are a staple of sweeps periods on TV, but we’ve never seen one quite like this.

As Stephen Colbert was talking about the flooding in Illinois and Missouri on “The Colbert Report” Wednesday night (May 4), he was suddenly seized by the need to use the restroom (as can happen when you’re talking about torrents of water flowing downstream). One problem: He couldn’t find the bathroom key.

After apologizing for the interruption — and urging his viewers to donate to the Red Cross to help both those affected by the floods and by the devastating tornadoes in Alabama and Mississippi — he went off in search of the key. “You guys can just watch Letterman or something,” he said.

And wouldn’t you know, a few seconds later, there was Colbert on the “Late Show” set, rummaging through Dave’s desk in search of the elusive key. Colbert later explained that Comedy Central and CBS were both owned by Viacom (which actually isn’t true anymore, but for the sake of comedy we’ll let it slide), and they all have to use the same bathroom.

The bit played out simultaneously on both shows, with Colbert interrupting Letterman’s monologue as he entered the studio and then a couple minutes later as he returned the key. While he was offstage at the Ed Sullivan Theatre, meanwhile, he returned to the “Colbert” set … only to find that Katie Couric was already in the bathroom, brushing her teeth.

Here’s how the crossover looked on each show:

Posted by:Rick Porter