NBC celebrates the one bright light of its new season by offering viewers three consecutive episodes of the funny, offbeat comedy “My Name is Earl” (7:30 p.m. through 9 p.m. today, NBC). For the uninitiated, Earl (Jason Lee) is a hangdog petty thief who wins the lottery, discovers the notion of karma and sets about righting the hundreds of wrongs he has committed through the years.

“Earl” deviates wildly from the normal sitcom universe of comfortable affluence. Earl and his brother, Randy (Ethan Suplee), drive a car held together by rust, and Randy takes great pleasure in buying used drinking straws at a swap mart. Earl’s greedy ex-wife, Joy (Jamie Pressly), has to rent a VCR to watch a video. And speaking of Joy, Pressly’s character has become my favorite new TV villainess.

Unlike most sitcoms, where life seems to converge on a single living room or kitchen, “Earl” sends its characters out on small adventures, allowing the story to verge on the mock-heroic. With his dimwitted sidekick, Randy – who in turn has his own sidekick, Catalina (Nadine Velazquez), a sexy motel maid – Earl becomes a comic, karmic Don Quixote. He may be deluded, but he’s on a righteous mission. And any show that pits contrition against joy is worthy of contemplation.

¢ The made-for-television drama “The Hunt for the BTK Killer” (8 p.m. Sunday, CBS) stars Robert Forster (“Jackie Brown”) as Wichita police detective Jason Magida, who was in charge of one of the most frustrating manhunts in history. Told in a series of flashbacks and confessions, Dennis Rader (Gregg Henry) explains how he perpetrated 10 murders that went unsolved for more than three decades.

Saturday’s highlights

¢ Major League Baseball Divisional Playoffs (7 p.m., Fox).

¢ Scheduled on “48 Hours Mystery” (9 p.m., CBS): an office party ends in death.

¢ “Napoleon Dynamite” star Jon Heder plays host to “Saturday Night Live” (10:30 p.m., NBC). Ashlee Simpson will pretend to sing.

Sunday’s highlights

¢ Scheduled on “60 Minutes” (6 p.m., CBS): former FBI director Louis Freeh; cat burglars; NASCAR.

¢ Legal troubles for Bree’s mother-in-law on “Desperate Housewives” (8 p.m., ABC).

¢ Larry’s inappropriate gift provokes a jealous husband on “Curb Your Enthusiasm” (9 p.m., HBO).