Julie Chen Julie Chen

Big Brother producers are adding another level of treachery a la The Mole with what they've labeled a "saboteur."

When the show premieres Thursday, July 8 at 8/7c on CBS, one of the houseguests will have a separate mission: to sabotage the rest of them. This player's goal will be unknown to the rest of the cast. Viewers, however, will learn the person's identity July 15 — when the first live show airs.

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The show — one of summer TV's guiltiest pleasures — features contestants living with and competing against each other to win $500,000. Their every move is captured on cameras rolling 24 hours a day.

Viewers will be able to influence the game by suggesting ways the saboteur can best wreak havoc on the players. Because each week a different houseguest is evicted, the longer the secret player can stay in the game and maintain his anonymity, the more remunerative it will be for him.

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Executive producer Allison Grodner calls the person "a game piece ... that will make life for the houseguests harder than ever before."

What do you think of the new twist?