Week 18

The final four contestants go home to prepare for a marathon, but some of the players have trouble staying on track when surrounded by all of the distractions of home. And one contestant gets a special visit from chef Curtis Stone. Later, they return to the ranch to run the 26.2 miles, cheered on by family members as well as each of their favorite past season contestants - season 5 winner Ali Vincent, Season 2 winner Matt Hoover, and Season 7 contestants Mike Morelli and Sione Fa. The winner finishes in record time, breaking a "Biggest Loser" marathon record. Then it's the very last "last chance workouts" with trainers Bob Harper and Jillian Michaels before a final weigh in determines who the two definite finalists will be - and which two contestants fall below the dreaded yellow line, leaving America to vote which one will be the third finalist to compete for the grand prize of $250,000.