Season 12 of MASTERCHEF is all about redemption, when All-Star competitors from the last 11 seasons return to the show to see if they have learned from their past mistakes. For the first time ever, MASTERCHEF is re-opening the door to some of the most memorable and talented cooks in the competition's history, including two MASTERCHEF Junior Edition cooks now competing as adults! 40 chefs get called back to audition, but only 20 will claim a coveted white apron. The returning chefs compete in groups of four in head-to-head audition battles. In each round, the two chefs that create the most impressive comeback dish will secure a spot this season.

The audition battles continue this week on the most competitive season of MASTERCHEF yet. For those who fell short in past seasons, these auditions are a chance to fulfill their culinary dreams. This week, three chefs who competed on MASTERCHEF JUNIOR enter the kitchen for the first time as adults.

In the first elimination round of the season, all 20 chefs must cook something inspired by the dish that originally sent them home. The chef that recreates their elimination dish in the most elevated, refined and skillful way will win immunity.

This week, the chefs face their first mystery box challenge of the season. Season Seven winner, Vegas restaurant owner and cocktail connoisseur Shaun O'Neale, returns to the MASTERCHEF kitchen to dish out the challenge. The chefs have 60 minutes to cook three identical dishes using the spirits they receive in their mystery box. On the line are immunity or elimination, as the chefs compete to create a dish with their respective spirit as the star.

For their first team challenge, the top 18 travel to the U.S. Coast Guard Base in Los Angeles. The chefs must collaborate to create a hearty and delicious lunch for more than 100 brave women and men. One contestant will be eliminated.

Chef Gordon Ramsay shares his secret love for meatless, dairy-free dishes by demonstrating his famous Beef Wellington transformed into a vegan dish made out of beets. Chef Ramsay then challenges the contestants to create a top-notch vegan dish, using their knowledge of flavors and techniques.

The 16 remaining chefs are challenged to cook a Southern cuisine dish inspired by complex flavors from countries around the world. Award-winning chef and Southern fusion restaurateur Tiffany Derry also stops by the kitchen.

One chef selects a dessert for each of his or her fellow competitors to bake to perfection. Anything less will force the contestants to face elimination.

More than 100 cowboys and cowgirls in Horse Town, U.S.A., gather for the MasterChef rodeo, where the Top 14 chefs divide into two teams to create the best steak and sides. The team that doesn't live up to the cowboys' standards faces the possibility of elimination.

The remaining chefs are challenged with a "Winner's Mystery Box," curated by the Season 3 Champion, Christine Ha. The contestants are tasked with creating a Michelin-starred Vietnamese dish, but there's a catch - they must use every ingredient given to them.

The Top 12 chefs are challenged to a tag-team cook-off, as they approach the halfway point in the competition. They're tasked with choosing a partner and cooking three menu items from Gordon Ramsay's Michelin-starred restaurants, taking turns against the clock.

In order to secure a spot in the Top 10, the remaining chefs partner with GrubHub to elevate a traditional take-out dish into a gourmet concoction.

Keeping up with culinary trends and tapping into nostalgia, Chef Ramsay brings a new challenge to the kitchen. The Top 10 chefs are tasked with elevating traditional gas station and road trip snacks into gourmet dishes.

The Top Nine chefs are faced with another Winner's Mystery Box challenge, this time from MasterChef Season Nine winner Gerron Hurt. With no more immunity pins up for grabs, each contestant must create a dish that packs heat using an assortment of chilies and peppers.

The top eight chefs are paired together and must communicate on opposite sides of a wall to create identical dishes.

The chefs must take over Wolfgang Puck's kitchen at Spago restaurant in Los Angeles.

The top five chefs are faced with tow separate elimination challenges in the semifinals: a baked Alaska and an intricate lobster tortellini.

The chefs who advance to the finals prepare an appetizer and entree with the support of Graham Elliot.

The three remaining chefs rush against the clock to complete their final entree and whip up a gourmet dessert with the help of former judge Christina Tossi; a new champion is crowned.