The Biggest Loser (season 4) is the fourth season of the NBC reality television series entitled The Biggest Loser. The fourth season premiered on September 11, 2007 with 18 overweight contestants in a weight loss competition for an ultimate prize of $250,000. The Biggest Loser campus was located at California State University Channel Islands in Camarillo, California.
The season four contestants were divided into 3 teams: the Red team, led by trainer Kim Lyons; the Blue team, led by trainer Bob Harper; and the Black team, led by trainer Jillian Michaels. The teams were formed on the first episode, with the Red and Blue teams being selected by the two players who had won a foot race across the desert. The Black team was formed with the 6 remaining contestants who were not selected for the Red and Blue teams. While the Red and Blue teams returned to the Biggest Loser campus, the Black team was left behind, believing that they had been eliminated already. Instead, they remained in the desert and trained in secret with their trainer, Jillian, until they arrived on campus for the weigh-in at the end of week 2.
The contestants start off their weight-loss journey by being dropped off in the middle of the desert, while their trainers standby about a mile away from them. The first two to reach their trainers will become the team captains, allowing them to pick their five teammates. However, this means the six remaining contestants have to be sent home, but Jillian Michaels returns to let them in on a little secret.
Bob and Kim prepare their teams for this week's challenge: racing up the stairs of a 10-story building. With immunity as the prize, both teams will have to do their best. Meanwhile, the secret black team, trained by Jillian Michaels, is finally revealed to the other contestants, who will join them in competing for the title of "The Biggest Loser" and $250,000.
When the teams are put in a room full of tempting, unhealthy foods, they will have to decide in four minutes if it is worth it or not to eat the most calories in order to win a three-pound pass which can be used to their advantage at the weigh-in. In the challenge, the contestants will compete in three different 100-meter heats against a yellow team formed by three kids, where the winning team will win a phone call home.
Another food temptation this week puts the trainers to the test instead of the contestants. Should Bob, Kim or Jillian give in to the temptation, it will give their team a 15-second advantage in the physical challenge. The challenge consists of the contestants running up and down a hill to reach their team flag in the fastest time. However, there is one catch: the teams will have to outbid each other with a faster time in hopes that someone will wager lower and lose, which will end up knocking out a team.
Alison surprises all three teams with an exotic getaway vacation, but they soon learn that they will be faced with temptations and challenges unlike any they have faced at the campus. Later, after the weigh-in, those who lost will try to forge an alliance with the others before deciding who to vote off.