Survivor first introduced the hidden immunity idol in its eleventh season. The hidden immunity idol is a talisman hidden near the camp which provides a one-time antidote from being voted out if revealed immediately after the fatal vote. When used properly, it's an extra life in a game of survival, the most powerful tool one can attain in the quest for a million dollars.
The logical thing to do after finding the hidden immunity idol is to hide it, shut your mouth, wait until you are on the chopping block, then play the idol to simultaneously save yourself and off your nemesis.
Almost without fail, however, the castaway who discovers the hidden immunity idol ends up spilling the beans to his tribemates. The usual pattern: one castaway finds the hidden immunity idol up in a tree or under a rock, celebrates gleefully with the cameraman, gives an emotional interview about the power of the idol and her newfound position in the game, sits on it contentedly for a day or two, then reveals it to multiple competitors under the pretense of currying favor and building alliances.
There are many fascinating aspects to
Survivor, but perhaps the most compelling is watching how people deal with the extreme but extremely finite desolation. All the castaways are thrust into a physically, mentally, and socially exhausting crucible without any relationship to their teammates/adversaries, without a friend in the world. There is a million dollar prize at the finish line, but 90% of contestants lose sight of that goal and make decisions to placate temporary human relationships that will be irrelevant within a week or two. The choices they make will affect the rest of their lives, yet they often make the ones that will only benefit them for a few days. Loneliness, even in its most temporary form, is just too hard for most people to face. Consciously or subconsciously, they'll make any sacrifice for companionship, however fleeting it may be. Even the diabolical Russell Hantz couldn't keep his idols to himself.
The notable exception came last season, when Boston Rob Mariano found the idol early on and hid it until the last moment it was playable. Rob credited his performance, the most dominant start-to-finish run in
Survivor's 23 seasons, to the strength his family gave him while cast away. Rob played the most heartlessly efficient, singularly focused game in Survivor history, but only because he never felt alone.