Includes all episodes and the 20th Anniversary Special sneak peek by Morgan Spurlock.

In South Park's 86th episode, Butters, a.k.a. Professor Chaos, concocts various schemes to wreak havoc but abandons each when he learns that ""The Simpsons already did it."" By the end of its historic 20th season, The Simpsons comprised more than 440 episodes, so imagine the challenge for the writers to come up with something they haven't already done or resist the temptation to make every episode a clip show. So it's heartening to see that after two decades, The Simpsons still draws inspiration from such highbrow sources as Stanley Donen's 1967 sophisticated romantic comedy Two for the Road (the episode ""Dangerous Curves""), Peter Jackson's Heavenly Creatures (""Lisa the Drama Queen""), and Ayn Rand and Shakespeare (""Four Great Women and a Manicure""). The flashback episode ""Take My Life, Please,"" marks the show's switch to high definition and the debut of a spectacular new opening with some of the best couch gags ever (except for one that Comic Book Guy inevitably declares to be the worst). Episodes such as ""Sex, Pies and Idiot Scrapes"" (Homer and Ned become bounty hunters), ""Lost Verizon"" (the family chases Bart to Machu Picchu), and ""Waverly Hills 9-0-2-1-D'Oh"" (Alaska Nebraska???) are good; they're just not Simpsons good. But those who claim that the show has lost its heart are directed to the touching ""Dangerous Curves"" and ""Eeny Teeny Maya, Moe,"" in which Moe falls in love with a little person. The voice work by the core ensemble is as inspired as ever. Dan Castellaneta won an Emmy for ""Father Knows Worst."" Notable guest stars this season include Denis Leary as himself, Emily Blunt as Lisa's partner in fantasy in ""Lisa the Drama Queen,"" Anne Hathaway as a goodhearted older girl who captures Bart's affections, and Jodie Foster as the rebellious voice of Maggie in ""Four Great Women and a Manicure."" Two separate episodes feature rousing renditions of the show's theme performed by Fall Out Boy and by a cappella group Canvas, respectively.

It makes good business sense to release The Complete 20th Season in advance of seasons 13 to 19. When an animated series ties (and has now surpassed) Gunsmoke as prime time's longest running show, attention must be paid (and exploited). But unlike previous sets, there are none of the extras Simpsonites have come to expect save for a less-than-4-minute ""sneak peek"" at Morgan Spurlock's excellent 20th-anniversary special. In trying to come up with just the right clever thing to say about that, one must look, as with everything in life, to an episode of The Simpsons, the one in which Bart discards a Where's Waldo book that eschews the usual crowd scenes for a single life-size illustration of Waldo. ""Man,"" Bart remarks, ""He's not even trying anymore."" --Donald Liebenson