This is one of the least genre-bending episodes of Community — no animation, no tricks with chronology — and it has some darkly contemplative moments, but it also has a lot of comic high points. There's Annie insisting on creating a Texas accent and back story to go with the name on her fake ID. And there's Jeff and Britta's sniping over the lameness of certain bars and drinks. (Jeff suggests going to a place that's "fun, divey, but not staph-infection divey," Britta mocks his "high-maintenance poseur drinking," and Troy says, "I can't wait to understand these arguments!") I confess to taking part in such debates, and they do get ridiculous pretty quickly.

"Mixology Certification," in which the study group takes Troy to a bar to celebrate his 21st birthday, is a great example of a field trip episode. The change in scenery emboldens some characters and shows others at their most vulnerable. This episode also helps establish Troy and Annie as the real protagonists of the series, as Community focuses less on second chances (Jeff returning to school after being disbarred) and more on the process of defining oneself as an adult.

Welcome to the “100 Best Sitcom Episodes of All Time,” a countdown for 2012. Each episode will get a separate blog post, counting backward toward No. 1. A list of the programs revealed so far is here (and on Pinterest ), and an introduction to the project is here .

"Mixology Certificate" ends with optimistic poignancy. Annie uses her alter ego to beat up on herself for not being adventurous and we see her crummy apartment for the first time — but we just know that she won't be stuck there forever. Troy ends up as designated driver, not experiencing the debauchery promised for his birthday, but instead realizing that he enjoys being a leader. (In retrospect, his scolding of Abed — "nobody likes a tattletale" — is a key moment in their relationship.)

Annie: Weird night, huh?

Troy: Yeah. Alcohol makes people sad. It's like the Lifetime movie of beverages.

• Poor Abed. First he gets a drink thrown in his face for sending mixed signals to someone hitting on him. Then he's stuck in the back seat of the car and ignored by a flirtatious Jeff and Britta. I'm most worried that he doesn't realize these things eventually happen to everyone.

• Would Shirley really have been a regular at that bar? "Mixology Certification" gets around the Joan Holloway Harris question by placing Shirley's drinking days in the past, presumably before the first episode of Community. I'm OK with this back story, if only for the moment when Britta tries to reassure Shirley that the revelation makes everyone "like her more" and Shirley isn't having any of it. It can be condescending to deny someone's shame. Besides, how can Shirley believe anything someone says in a place like this?

• Given the importance of drinking establishments in real-life communities, I wanted an episode set in a bar on this Top 100 list. As much as I like Cheers, it's not really about drinking.

• From imdb.com's description of "Mixology Certification":

When Senor Chang finds the fresh remains of a birthday cake in the study room, he vows to find the group. Written by NBC Publicity

I think I'm glad that was cut from the episode.