Big Brother (9pm, CBS) - In the 13th season opener, eight new house guests are introduced, plus some notorious pairs from previous seasons who will also play the game.

Rookie Blue (10pm, ABC) - A full moon brings the crazies out as Andy and Swarek track a disturbed man while looking into the theft of three severed heads from a medical lab. Andy tries to protect a young woman who may be the next victim, and ends up putting herself and Luke in harm's way.

Suits (10pm, USA) - Harvey goes rogue in order to fix a crisis with a client despite Jessica's desire to reign him in. Elsewhere, Mike turns to Rachel for guidance when he learns he'll be hosting a dinner for rookies, and important tradition at the firm.

Extreme Chef (10pm, Food) - A mountain challenge has three chefs, including Rocky Mount's Chef Jerome Brown, hiking up a steep hill with all their cooking supplies and diving into a frigid lake to catch fish.

Wilfred (10pm, FX) - Ryan gets his wallet back from his violent, porn-addicted neighbor (Ethan Suplee), who wants revenge on the thief, but who also wants a pal.

Louie (10:30pm, FX) - Louie searches for a new home in New York. Donna Hanover, ex-wife of former New York City mayor Rudy Giuliani, plays Louie's real estate agent.

Ugly Americans (10:30pm, Comedy Central) - Callie reluctantly becomes her baby sister's guardian when their estranged parents' reunion proves to be a short one.

Survivor: Nicaragua (8pm, CBS) - NaOnka and local girl Kelly Bruno engage in a small war over the hunt for the hidden immunity idol.

Modern Family (9pm, ABC) - When an earthquake strikes, Cameron and Mitchell see a way out of a costume brunch thrown by their friend Pepper, played by Nathan Lane. Also, Claire is trapped in the bathroom with a plumber and Manny undergoes a crisis of existential proportions on an outing with Jay.

Law & Order: Los Angeles (10pm, NBC) - The detectives are on the case after a cult member is stabbed to death. The cult's leader is questioned, along with the victim's cell mate and Det. Winters' wife, Lori. Terrence Howard has DA duty tonight.

Harry Loves Lisa (10pm, TV Land) - The premiere of a new reality series following the lives of married actors Harry Hamlin and Lisa Rinna. Adrienne has more about the show here.

Steven Seagal Lawman (10pm, A&E) - In the second season opener, Seagal and his team witness a head-on collision and search for a suspect in a double-homicide case.

Terriers (10pm, FX) - What is the best show on TV that you're not watching? This one. The Lindus conspiracy widens around Hank and Britt (left) in tonight's episode, as they have just 24 hours to fix the mess they're in or Mark will no longer be able to protect them (if you watched last week, you know the mess I'm referring to).

Top Chef: Just Desserts (10pm, Bravo) - Forget the challenges, watch to see which pastry chef breaks down in tears tonight. It will happen.

Also tonight, a new season of "Mythbusters" (9pm) starts tonight on Discovery, and new seasons of  "South Park" (10pm) and "Ugly Americans" (10:30pm) begin on Comedy Central. Here's a funny recap of Season 1 of "Ugly Americans."

American Idol (9pm, Fox) - Someone's eliminated, but Usher is the consolation prize.

Cougar Town (9:30pm, ABC) - Jules bonds with Grayson's new girlfriend, played by Sheryl Crow, and pleads with Grayson not to smother her and drive her away. Meanwhile, Jules' fancy new bathroom becomes the talk of the town.

Law & Order: SVU (10pm, NBC) - The case of a woman found murdered in her bed reminds Cragen of a case from thirty years ago. Benson and Stabler question the patrol cop from the case (Jaclyn Smith) and the prime suspect's ex-lover (Ann-Margret, left). 

The Locator (10pm, WeTV) - A pair of sisters from Cary look for
their brother, whom their mom put up for adoption after becoming
pregnant as a teen. 

In Plain Sight (10pm, USA) - In the season three premiere, Marshall and Mary (Mary McCormack) search for the gang member who shot Mary in last season's finale. Also, Donnie Wahlberg stars as a Boston thief who wants to straighten out his life for the sake of his son. Marshall (Fred Weller, right) is still as funny and charming as ever, and Mary's mother (Lesley Ann Warren) is still just as grating and annoying. 

Ugly Americans (10:30pm, Comedy Central) - Mark takes care of an orphaned demon and it triggers Callie's maternal instincts. 

"Ugly Americans," a sharp (and very weird) new animated series from Comedy Central, pulls off a nearly-impossible feat: it preaches on issues of racial and ethnic tolerance but without being the least bit preachy. And it's funny. (Preview below.)

The often crass and sometimes gross cartoon centers around Mark, a government social worker whose job it is to help new immigrants (werewolves, zombies, robots, floating brain stems, etc.) assimilate into life in New York City. Mark believes in his work, but does it with slapdash effort, and he's usually at odds with his overzealous immigration coworkers and the devils who run the place.