The final four players all return home to see their loved ones. Each player is a bit nervous about how they'll adjust to life at home considering what they'd gotten used to on the ranch. At the same time, Elizabeth, Frado, Patrick and Ada are anxious to see everybody.
Each of the players return home and watch videos of their journeys from day one on The Biggest Loser. The final four watch the videos with their families and tear up over how far they've come in such a short amount of time.
Ada's family watches Ada's video, which includes her opening up to Jillian about how her family makes her feel like a failure. Her mother begins to cry while watching Ada's transformation on the ranch. After the video, Ada tells her parents she hopes their relationship will get stronger.
It isn't all fun and games for the players while they are back home. They have to train for a marathon that they'll be running with the other final four players. They have only 30 days to prepare to run 26.6 miles.
Ada is having a harder time at home because since nobody is watching her back, she can eat more often when she gets bored. At least on the ranch, she was constantly staying active and had things to do. Ada's fear is she'll be at the final weigh-in and be the one who loses no weight.
Curtis Stone goes to Frado's hometown and agrees to cook a meal for Frado and his family. Frado wants to pay it forward and asks Curtis is they can make it into a charity event, where people can buy an invitation and donate money to their favorite cause.
Bob and Jillian are about to drop by the final four players' homes and see how they are doing with the change. Bob's first trip is to visit Frado, while Jillian heads to Elizabeth's hometown. None of the players know about the trainers surprise visits.
Bob and Jillian aren't just visiting the final four players to surprise them, but to give them a workout. Bob works Patrick out in the gym, reminding him that this Biggest Loser journey isn't only about him, but also his family. Meanwhile, Jillian is still not happy that Elizabeth moved in with her boyfriend as soon as she left the ranch. Elizabeth agrees that she hasn't been working out as much since the move.
Frado, Patrick, Ada, and Elizabeth all return to California and prepare for their very first Biggest Loser marathon. Ali is there to greet them at the starting line. After each player crosses the finish line, they will have the opportunity to donate $10,000 to their favorite charity.
As the miles go by, the players begin to feel the wear and tear of the long-distance run. Especially Frado, who experiences bad leg cramps and has to slow down. Patrick refuses to leave his running partner behind and is there to encourage him.
As each player runs the marathon, they are happily surprised to see friends and family on the sidelines waiting to greet them and motivate them to finish the distance. This is exactly what Ada, Frado, Elizabeth, and Patrick need to inspire them to keep running.
Ada is the first player to cross the finish line and she's happy that she beat Tara's record and now has the best marathon record for any female on The Biggest Loser. Patrick is the next to finish, followed by Frado and Elizabeth.
It's time for the final four players to weigh in one last time. Bob and Jillian are shocked that Ada has only lost 12 pounds since she went home for the month, which puts her below the yellow line. Patrick and Frado have lost enough weight to automatically be in the finals, but now Elizabeth and Ada have to depend on America's vote.