Contestants on the NBC reality weight loss show The Biggest Loser are threatening to quit after learning about a twist in the competition that could affect their shot of winning the $250,000 prize.

TMZ reports that nearly all of the show's remaining contestants walked off the set last week in protest after hearing that producers may bring previous contestants back to compete against them.

Sources tell TMZ the angry contestants don't think it's fair that "biggest losers" who already got the boot be given a second chance. The contestants bolted together in the middle of shooting an episode.

The show has shut down production for at least a week until producers figure out how to make sure the biggest loser doesn't end up being the show itself. 

Tags: Biggest Loser