December 17 the 30th anniversary of The Simpsons' series premiere, and to celebrate, the series' cable home FXX is going all out. Starting at 8 p.m. ET on Tuesday, Dec. 17 — precisely 30 years after the first airing of "Simpsons Roasting on an Open Fire" — FXX will air 661 episodes from the show's first 30 seasons, plus The Simpsons Movie and the animated short "The Longest Daycare," in sequence. It will break the longest TV marathon record The Simpsons previously set with the 600-episode marathon in 2016, according to FXX.

The Simpsons Movie will air between Seasons 18 and 19, and "The Longest Daycare," which is airing for the first time in syndication, will air at 11:30 a.m. ET on Dec. 28.

The marathon is being called the "Plus+Size Holiday Marathon," to celebrate the show's move to Disney Plus as its new streaming home.

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The marathon will end at 4:30 p.m. ET on Dec. 31, at which time FXX will air a "Best of the Marathon" marathon beginning with an encore presentation of The Simpsons Movie and The Longest Daycare, followed by the 11 greatest The Simpsons episodes as determined by the series' creators and viewer usage on FX's former "Simpsons World" on-demand portal.

The Simpsons is available to stream on Disney Plus.

<em>The Simpsons</em>The Simpsons

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