When 30 Rock premiered its fourth season last October, some wondered if the show had lost its edge. As the weeks go by, though, it just keeps getting better. Tonight, it outdid itself. Inside, Liz Lemon's sleep-eating tour de force.

Tonight's episode brought the debut of Liz and Frank as roommates, as he sought refuge in Le Château de Lemon after losing his apartment in a fire. Liz discovered, however, that Frank's crutch—what he uses to deal with stress—was smoking, and she wasn't having it. But what about her habit of eating junk food to deal with her own problems? The solution, it appeared, was for each of them to quit their vices cold turkey, and support each other in their collective efforts.

Soon thereafter, though, Liz suspected that Frank was sneaking cigarettes behind her back, so she decided to videotape their living room one night and see if she could catch Frank in the act. When she woke up the next morning and found there to be three fewer cigarettes in Frank's pack than the night before, Liz proudly waltzed into the office with her camera and prepared to expose Frank as a cheater.

Well, things didn't go exactly as planned. The hilarious scene, where everything was revealed, is below.

[30 Rock]