Irene Alvarado

This week, one eliminated contestant returns and the remaining players are split into four teams -- red, blue, green and black. Each team will be led by one of the four trainers -- Bob Harper, Jillian Michaels, Cara Catronuova and Brett Hoebel. While Bob takes his team to spin class and Jillian takes hers to work out at the beach, Brett leads his group on a hike and Cara heads to a boxing ring and has one of her players fight against a longtime boxer. Later, the four teams square off in a difficult challenge involving ropes and weights, and then gameplay at the weigh-in doesn't turn out the way one contestant expects, and another player is sent home. Alison Sweeney hosts the series.

This week kicks off with a pop challenge in which contestants have to estimate the length of a mile. The winning team gets a night out on the town, Hollywood style, while the other players have to stay behind and clean the ranch. Later, the teams race to light up a "Biggest Loser" board in a challenge that gives a stiff penalty for the losing team -- no votes at the elimination. Then one trainer gets shocking news at the weigh-in, and after an emotional elimination, host Alison Sweeney delivers some very exciting news to the contestants. Trainers Bob Harper, Jillian Michaels, Cara Castronuova and Brett Hoebel also star.

Two new trainers and a compelling new twist deliver a game-changing season like nothing viewers have seen before when season 11 premieres with twenty-two contestants -- eleven family and friend teams of two. After the first challenge, contestants are given the unprecedented opportunity to choose whether to work out with trainers Bob Harper and Jillian Michaels at the ranch - or work out at a secret location with two unknown trainers and get four weeks of immunity. What ensues is a riveting ride of intense emotions, surprising turns and "can't miss" moments as the two groups fight their weight loss battles separately with two sets of trainers equally committed to giving these players a new lease on a healthier life. The contestants include an Olympic gold medalist, identical twin policemen, a pastor who wants to spare his overweight son from the challenges he faced because of obesity, and a woman who has lost pregnancies because of her weight and wants more than anything to be a mother. Alison Sweeney hosts the series.

Each team has to pick a team captain, who will have many responsibilities during the week, and only two players from each team can work out with a trainer. The teams first square off in a pop challenge involving 13 tiered cakes, and later, the contestants meet host Alison Sweeney at a mud pit where they have to make their way across the pit while balancing on a step -- without touching the mud. Several contestants have heart-to-heart talks with their trainers, opening up more about the individual personal struggles they had before coming to the ranch, and later, another player is sent home following a weigh-in with some surprising weight loss numbers. Trainers Bob Harper, Jillian Michaels, Cara Castronuova and Brett Hoebel also star.

After four long weeks, the "unknowns" move to the ranch and are reunited with the other contestants, who get to meet the new trainers for the first time. Host Alison Sweeney explains that the ranch contestants will be safe this week if they collectively lose more than 48 pounds, but for the "unknowns," they will be facing their first elimination all season. And both teams only get to see their trainers once this week. The "unknowns" experience some surprises while settling into their new home, and a secret is revealed about how one contestant has lost so much weight. A challenge involving weights shows which team stacks up to be the best, and later, everyone weighs in and finds out whether one or two players will be going home.