In Seinfeld: Season 4, ”a lot of crazy ideas started to make sense,” says Jerry Seinfeld, as the quirky show with a cult following became a cultural phenomenon after moving to must-see Thursday. Once Jerry, George, Kramer, and Elaine tested their self-control in ”The Contest,” there was no going back, since, as writer Peter Mehlman points out in an Inside Look at ”The Implant,” ”If you can do 22 minutes on masturbation, you can pretty much do anything.” When the network tried to rein in verboten story lines, the gang boomeranged their stale suggestions into dialogue and parodied their corporate likenesses in a season-long arc about Jerry’s sitcom pilot. ”The network’s kind of like your aunts and uncles,” Seinfeld says in the pop-up notes for ”The Shoes.” ”They are superiors, but we don’t really have to listen to them.” (Uncle Leo must be crushed.)

EXTRAS An assortment of riches, including commentaries, outtakes, interviews, deleted scenes, promos, a double-dip of ”The Handicap Spot” (one with the original Mr. Costanza, John Randolph), and an Easter egg revisiting Julia Louis-Dreyfus’ parking space tiff with Tom Arnold.