Award-winning US comedy "30 Rock" bowed out after seven seasons Thursday, with a double helping of the cult TV show starring Tina Fey and Alec Baldwin.

The multiple Emmy-winning comedy show -- about the cast of a TV comedy sketch show -- has featured a who's who of guest celebrities over the years, including Oprah Winfrey, Jennifer Aniston and Calvin Klein.

Its last hour-long episode was twice the usual length, bringing down the curtain on a show named after 30 Rockefeller Plaza, the New York address of NBC television studios.

"30 Rock" first aired in October 2006, loosely based on writer Fey's years on "Saturday Night Live" -- the long-running show where she famously imitated then Republican vice presidential nominee Sarah Palin.

In the series, Fey plays Liz Lemon, the neurotic head writer of the show-within-a-show fronted by Tracy Jordan -- played by Tracy Morgan -- while Baldwin plays Jack Donaghy, the suave and meddling TV company executive.

Other celebrities who appeared on the Thursday night show over the years included Whoopi Goldberg, Matthew Broderick, Julianne Moore, Matt Damon and Susan Sarandon.

While the show built up a cult following for its off-the-wall, often politically incorrect humor, it never attracted the mass audiences of shows like "Friends" or more recently "Modern Family."

But it was always a critical success, winning three successive best comedy Emmys in 2007, 2008 and 2009, when it also won the Golden Globe for best TV comedy show.

Fey herself won the best comedy actress Emmy in 2008, and the Golden Globe in the same category in 2008 and 2009. Baldwin won best actor Emmys in 2008 and 2009, and three Golden Globes in the same category, in 2007, 2009 and 2010.

Only last weekend, they garnered their latest prizes, at the Screen Actors Guild awards in Los Angeles, where Baldwin won best comedy series actor and Fey best comedy series actress.

The Washington Post's TV critic Hank Stuever, in a farewell review this week, said the show "offered some of the sharpest, up-to-the-minute cultural criticism around."

He quoted from Thursday's final double-helping episode, which he said "finds tidy and appropriately ironic endings for nearly all of its characters," including a moving scene between Morgan and Fey.

"We were forced to be friends because of work, and we're probably not going to hang out after this," she tells him.

"Working with you was hard, and you frustrated me and you wore me out, but because the heart is not properly connected to the human brain, I love you and I'm going to miss you. But tonight might be it."