Janice Dickinson shocks the models at a red-carpet challenge; at a photo shoot, the women pose as celebrity couples. Later, another model is eliminated from the competition.

The BAU investigates a serial rapist who had been attacking young women at religious schools and stopped for six weeks. He has resumed his attacks, but is now targeting a different demographic of women. Elle makes a decision that could end her career with the BAU.

Put simply, this episode is vintage, explosive MythBusters. Adam and Jamie have unfinished business from their Shark Week special, where they shot and then exploded a scuba tank. But they've always wondered if a ruptured cylinder — carefully aimed — can really cause the massive damage some people claim. Meanwhile, Tori, Grant and Kari go back in time to test some prototypes from the past. They all sound highly dangerous, and they probably are ... After all, they're tinkering with engines fueled by gunpowder!

Cartman, South Park Elementary’s new hallway monitor, takes it personally when he finds out that a teacher has been kissing a student in his jurisdiction. He helps Kyle stop his little brother’s affair with his “Nice” hot teacher.

The teams are shocked to learn that the gym has been locked for the week, which prompts Bob and Kim to teach them that they can workout anywhere without using the gym. Meanwhile, the Blue Team attempts to break their losing streak by winning the weekly challenge at the Los Angeles Coliseum.

Tonight Stephen welcomes former special assistant to President Bush and author of "Tempting Faith: An Inside Story of Political Seduction", David Kuo.

Fifteen new contestants are introduced for Top Chef's second season in Los Angeles by new host Padma Lakshmi. Guest Judge: Harold Dieterle. QuickFire Challenge: Create a Dish Using the Flambé Technique. Elimination Challenge: Create a Dish Using all Five Mystery Box Ingredients.