* Law & Order: Special Victims Unit (10 pm/ET NBC)
The month of March fittingly brings the return of Stephanie March, who begins reprising her role as ADA Alex Cabot in the first of several episodes. Benson and Stabler are shocked to see her at a crime scene, where she's filling in for the temporarily reassigned Greylek. Tonight Alex tackles the case of a murdered pediatrician who had been found guilty of molesting several patients. Shortly after his conviction, he filed a lawsuit against the NYPD, claiming they hesitated to take legal action against him.
* The Biggest Loser: Couples (8 pm/ET NBC)
In a move that's sure to prompt dread-filled memories of elementary school, the contestants are surprised with a pop challenge that will have an effect on this week's weigh-in. Perhaps to help them recover from the stress of the first challenge, the players then compete for a day of luxury and spa treatments in the next challenge, a relay race. But all the relaxation in the air quickly fades when a contestant has a blowup with her trainer.
* WCG Ultimate Gamer (10 pm/ET Sci Fi)
Most reality competitions have ditched reality as we know it, and video games are more realistic than ever. Merge the two and a game show is born! Twelve gamers move into a loft and vie for cash and prizes in rounds of video games and real-life simulations based on the games. In the opener, the gamers face off in Rock Band 2 challenges with, appropriately enough, the Donnas turning up as guest judges.
* How the Earth Was Made (9 pm/ET History)
Anyone who has ever been to New York City and walked through downtown Manhattan would - Central Park aside - find it easy to lose sight of the fact that it is built upon a chunk of earth. It seems as though the city had been carved by human hands from concrete and steel. This hour goes below the surface to examine its geological history and how everything man-made was determined by the physical landscape. Also examined is its prehistoric connection with Africa.
* Jeopardy! (7 pm/ET check local listings for time and channel)
Like Nigel Tufnel in This Is Spinal Tap, the classic game show is turning it up to 11. Why 11? Because tonight marks the start of what should be 11 great episodes of the classic game show, beginning with a celebrity round featuring Tom Bergeron, Elizabeth Perkins and Aisha Tyler competing for charity. Tomorrow, the Tournament of Champions gets under way with former winners returning for a shot at the $250,000 grand prize. The tourney concludes March 24.