SUNDAY'S MUST-SEE

"American Body Shop" debut (Comedy Central) or "Flight of the Conchords" (HBO), both 7:30 p.m. Two terrific comedies offer the same kind of comedy — dry and quiet, with no stars, no studio audience and an oddly deceptive kind of humor. This is the fourth week of "Conchords," and it continues to be a terrific surprise. We see three New Zealanders, scrambling in New York. Two are in an odd pop-music duo, occasionally breaking into songs with witty lyrics; the third is their immensely inept manager. One of the guys, Bret, has landed a day job holding up signs. He's apparently quite good at it, so he's been mentoring a new sign-holder named Coco. Now he's fallen for her. (This is understandable, because she's played by Foster Sutton, a charmer who won a Tony in "Thoroughly Modern Millie.") Their manager has decided she's the Yoko Ono who will break up the group. That becomes a self-fulfilling prophecy, in a wonderfully offbeat half-hour. The problem is that "American Body Shop" is almost as funny, in the same way. Like "Conchords," this is a quiet comedy that has its characters accepting absurd situations stoically. This one is a pseudo-documentary, set in an auto-body shop. The safety record has been horrendous, as flashbacks keep showing us. Now an insurance representative demands immediate change.

OF NOTE

"Harry Potter and the Prisoner of Azkaban" (2004), 5 and 8 p.m., ABC Family. As the world keeps talking about the new Potter book and movie, here's a fresh chance to see the third film.

"Big Brother 8," 7 p.m., CBS. Here's the second night for this peeping-Tom reality show, which debuted Thursday.

"The Simpsons," 7 p.m., Fox. Marge takes up role-playing games and is promptly obsessed.

"Desperate Housewives," 8 p.m., ABC. Just as Susan heads out on a weekend with Ian, Mike comes out of his coma. Edie is there to embrace him, in a rerun that's worth catching, despite a silly Little League subplot.

"Without a Trace," 9 p.m., CBS. A high school basketball star disappears, shortly after winning a big game.