Two of the most notorious “mad scientists” in Top Chef history face-off once again, Top Chef All Stars winner Richard Blais and competitor celebrity chef Marcel Vigneron. First, Marcel challenges Richard to make a dessert featuring both a hot and cold component while Richard chooses to challenge Marcel to make one of his specialties, a burger. And for their duel that will decide who moves on to the finale, Richard and Marcel must concoct a three-course meal specifically designed to entice each of the judges’ senses. Although Richard won the title when they competed against one another in Top Chef All Stars, never underestimate the power of revenge!

Both finalists in their respective seasons, Los Angeles Chef Brooke Williamson and Las Vegas Restaurant Consultant Shirley Chung were mere inches from victory, but the title slipped through their fingers. Now is their time for redemption. First, Shirley challenges Brooke to a ‘weird shellfish’ showdown and then Brooke attacks Shirley’s Achilles heel and asks her to make a vegan dessert. For the Duel that determines who goes on to the finale, the Chefs must step under the big top making dishes based on the circus to impress the judges and special guest P!nk. Neither Chef wants to go home empty handed again.

Revenge is a dish best served… well, any temperature on “Top Chef Duels.” DC Restaurateur Mike Isabella and LA Restaurateur Antonia Lofaso have a long, storied ‘Top Chef’ history. Besides discovering that they are cousins on All Stars, Mike’s victory prevented Antonia from moving on to the finale. Now can she take him down in the duel? First Antonia challenges Mike to make a better rice ball, then Mike gives Antonia a fish and shellfish butchery challenge. For the Duel, these competitive cousins go head-to-head in an Italian-themed smack down. Michael Chiarello joins the judges as well as the Chefs’ families to pick the winner. Who can win the family feud?

Old rivalries die hard. Los Angeles Chefs Stefan Richter and CJ Jacobson duked it out on “Top Chef Seattle” and enter this duel far from friends. Stefan first challenges CJ to cook with smoke, and then CJ asks Stefan to use products that remind CJ of Stefan… the backsides of animals. For the Duel, CJ and Stefan go back to nature for a foraging-themed meal to impress celebrity superstar Shailene Woodley and the rest of the judges. The taste of victory will be even sweeter thanks to the bad blood between these two.

These “Top Chef Masters” competitors and long-time friends take the duel to a whole new level. Takashi challenges David with an ingredient for which he is well known, the egg. David reciprocates with a test based on crab that must be prepared three ways. Then for the Duel, guest judge Andrew Zimmern offers up some of the most bizarre ingredients for their meal. Having to cook with unfamiliar products will push these Masters to their culinary limits.

When two chefs known for their tempers face off, it is bound to get hot in the kitchen. First, Dale challenges Tiffani to relive a past failure of hers in preparing dim sum. Then Tiffany counters with a contest based on an American canapé and classic cocktail. For the Duel, featuring guest judges Rob Zombie, Scott Ian and Gary Holt, the chefs must prepare a vegan meal and service will get hard core as one Chef will be rocked. These “Top Chef All Stars” are out to prove that the third time’s the charm.