TODAY'S MUST-SEE

"Mad Men" season-finale, 7 p.m., AMC. This Emmy-winner wraps up its second season amid change. Don has spent two episodes in California, ignoring his Manhattan ad agency. He wants to leave his wife (who threw him out after an affair) and marry a young woman he just met. Meanwhile, there's more change at work. Peggy has her own office now; the partners (minus the missing Don) have made an offer to sell.

"The 40-Year-Old Virgin" (2005), 7 p.m., NBC. In the one week without Sunday-night football, NBC reruns a movie. Steve Carell has the title role, with Catherine Keener, Paul Rudd, Elizabeth Banks, Seth Rogan and more. Carell wrote it with director Judd Apatow. This launched Apatow's hot streak as a director ("Knocked Up") and producer ("Talladega Nights," "Forgetting Sarah Marshall," more).

OF NOTE

Baseball, 2 p.m., Fox. The fourth World Series game has Tampa Bay at Philadelphia.

"True Blood," 6 p.m., HBO. There are some good moments early as Sookie struggles to learn if Bill has survived the fire in the vampire home.

"Entourage," 7 p.m., HBO. In a so-so episode, Ari must decide whether to accept the offer to run a movie studio.

"My Fair Wedding" debut, 7 p.m., WE. The bride has been planning her wedding for months. Now event-planner David Tutera arrives, shudders at the colors (green and purple) and starts over. It's an OK hour, with likable people.

"Nature" season opener, "White Falcon, White Wolf," 7 p.m., PBS. Filled with stunning pictures, this film captures the respite between nine-month winters in the Canadian Arctic. In three families (wolves, gyrfalcons, snowy owls), we see a lazy dad, valiant mom, wandering pup and more.

"Cities of the Underworld," 8 p.m., History Channel. England, it seems, is full of underground tunnels where evil things may or may not have happened. Here's a moderately interesting tour.

"Masterpiece: The Last Enemy," 8 p.m., PBS. It's a rough week for Stephen, probing a cover-up alongside his brother Michael and Michael's wife Yasim (who was Stephen's lover when both thought she was a widow). It all makes sense in next week's finale.