Caroline Rhea returns to welcome fourteen new players to The Biggest Loser and to host them at their stay at the new ranch. After being faced with a room of tempting food, the players discover a twist in the game - this time it's men vs. women! The women, who will always wear Red, will be trained by Jillian Michaels, while the Blue team, the men, will be put to the test by Bob Harper. Later, the new teams compete in the first challenge of the season - a competition that takes place in a jet so that the contestants can experience what it feels like to weigh nothing! At the end of this 90-minute episode, one of the hopefuls will be voted off of their team. Who will survive the battle of the sexes Biggest Loser style? 

The battle of the sexes continues as the 12 remaining contestants must overcome injuries and trainer disputes. Another food temptation tests their resolve; they have to decide if they want "the gravy train" or the next physical challenge, which requires the teams to travel up and down the aisle of a moving railroad train.