This time, 50 contestants are chosen - one from each state in the U.S. Kim Lyons replaces Jillian as the new trainer. The contestants learn that only 14 of them will get to stay at the ranch, sending the remaining 36 back home to compete on their own, with a chance of returning to the ranch to win the $250,000 grand prize.
The contestants take a trip the beach in order to get away from the ranch. After Bob and Kim put them all through a series of difficult workouts in the sand, the contestants realize it's not all fun at the beach.
Bob and Kim teach their teams how to exercise and eat healthy while on a cruise vacation. Their weekly challenge will consist of them, the contestants, delivering room service orders all over the cruise ship for an opportunity to win time with their loved ones. In the end, Nelson is eliminated.
The red team begins to mentally fall apart from all the pressure, which leads to them refusing to follow Kim's lead, making her frustrated. Meanwhile, the contestants give the "temptation" a try to win a free pass and receive immunity for the week. In the end, Melinda is eliminated.
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. In the end, Amy is eliminated.
In order to keep their team together, one team will have to step it up after back-to-back losses. The weekly temptation will not make things any easier, as the losing team will be left without their trainer and have to order takeout for the next 72 hours. In the end, Ken is eliminated.
Caroline informs the remaining players that from this point forward, the Red and Blue teams are no more. The players will now be paired up with another and compete as a duo, and Wylie has the opportunity to decide who will compete as duos. At the elimination, no vote is necessary as Kai uses the immunity pass, forcing the elimination of Brian/Pam.
The remaining players at the ranch are shocked when Caroline Rhea informs them that some of the 36 players sent home at the beginning will be rejoining them. Two players join the competition at the ranch, and have to struggle to adapt to Bob and Kim's training. In the end, Bobby is eliminated.
As the players are narrowed down, Caroline reveals to everyone that they will now play as individuals. The remaining players receive makeovers and a photo shoot to showcase their new thin bodies. In the end, Marty is eliminated.
The players learn how to cook a healthy Thanksgiving dinner. Meanwhile, their challenge this week will involve the players putting on all the weight they've lost since they arrived at the ranch. In the end, Adrian is eliminated.
Bob, Kim, and season 2 winner Matt Hoover head over to their high schools to teach the kids about childhood obesity, proper exercise, and nutrition. Meanwhile, Bob and Kim talk to the school lunch ladies about replacing the unhealthy food options with healthier ones. They attempt to inspire the kids to change their unhealthy lifestyles and educate their families. In the end, Jaron is eliminated.
It's the final week at the ranch, and the remaining contestants prepare to return home. They will try to take what they've learned at the ranch and apply it to their every day lives to continue losing weight on their own.
After spending several weeks of diet and exercise with their trainers at the ranch, the final four contestants weigh-in for one last time to reveal who is The Biggest Loser and the winner of the $250,000 grand prize.