She’s back. Paula Abdul hosts the new talent showcase “Live to Dance” (7 p.m., CBS). Viewers can root for their favorite unknowns and gasp at some untalented wannabes as dancers work their way toward the grand prize of $500,000. The series also offers Abdul a chance to show that she’s more than the goofy, positive and occasionally addled judge she played on “American Idol. For CBS, “Live” is also a direct challenge to its network competition — ABC’s “Dancing with the Star” and Fox’s “American Idol.” For several years now, those are among the few network shows to challenge the ratings dominance of CBS’s scripted series. Should the Eye Network add “Live” to its list of top-10 shows, expect much wailing and gnashing of teeth in the executive suites of Fox, ABC and NBC.

• The success of cheaply made talent series has made it harder for networks to commit to complex dramas that have a little harder time finding an audience. That was made readily apparent when NBC dumped the superior cop drama “Southland” after one season. Happily, the drama found a new home on TNT, where “Southland” (9 p.m., TNT) enters its third season tonight.

• Anna keeps Ryan on ice so she can conduct tests on his hybrid baby on the second-season premiere of “V” (7 p.m., ABC). A serious and expensive-looking adaptation of a cult 1980s series, this new “V” lacks most of the goofy appeal of the original.

• TCM kicks off a month-long salute to producer Hal Roach with a 24-hour marathon of “Our Gang” comedies running from 7 p.m. tonight through 7 p.m., Wednesday. Also known as “The Little Rascals,” these shorts were a staple of children’s morning programming for decades. Over the course of the month, TCM will devote Tuesdays to Roach’s films and shorts, featuring Laurel and Hardy, his early TV films and his feature comedies, including the “Topper” franchise.

• TV-themed DVDs available today include “Life Unexpected: The Complete First Season.”

Tonight’s other highlights

• A wronged Roman (Russell Crowe) unleashes Hades on his foes in director Ridley Scott’s 2000 epic “Gladiator” (5 p.m., TNT).

• Two new trainers join the team on “The Biggest Loser” (7 p.m., NBC).

• Budget cuts loom on “Glee” (7 p.m., Fox).

• New friends may harbor dark secrets on “No Ordinary Family” (7 p.m., ABC).

• A career herpetologist gets a little too close to his work on “Dangerous Encounters with Brady Barr” (8 p.m., National Geographic Wild). New to its network.

• A grandfather’s meddling complicates a kidnapping case on “NCIS” (9 p.m., CBS).

• Crosby can’t teach his Jabbar to clean his room on “Parenthood” (9 p.m., NBC).

• The hunt for a movie star’s murderer on “Detroit 1-8-7” (9 p.m., ABC).

• The “Independent Lens” (9 p.m., PBS, check local listings) documentary “Men Who Swim” follows a band of Swedish men who combat midlife malaise with amateur synchronized swimming competitions.