In the annals of reality television, “The Moment of Truth” may be a milestone. Fox has come up with a cash-prize competition that is neither a game of chance nor a test of knowledge. It’s a pseudo-psychological trial by ordeal in which the contestants trade candor for dollars.

The set is similar to those used on “The Weakest Link” and “Deal or No Deal,” but the object of this game is to prod seemingly nice people to admit bad behavior. As family members and friends look on, the contestant is asked a series of embarrassing personal questions by the host. Truthful answers, as determined by a polygraph, are rewarded by cash, from $10,000 for the first, relatively banal queries to $500,000 for the marriage-busting kind.

The novelty of “The Moment of Truth” is not the lie detector. That was the conceit behind “Meet the Parents” (2000), the hit Ben Stiller comedy. NBC borrowed it for a short-lived dating show in 2002, “Meet My Folks,” in which suitors were interrogated by the parents of the date-seeking contestant.

What distinguishes the Fox series is that it blends the cooked-up psychodrama of behavioral reality shows like “Big Brother” on CBS and “The Real World” on MTV with the regimented good family fun of nighttime game shows like “American Gladiators” and “Deal or No Deal” on NBC and “Power of 10” on CBS.