you're on

You're On! was a Nickelodeon television game show which aired from 1998-1999. The show took a premise similar to Candid Camera; however, to adopt the format better for a children's game show, You're On! featured youth contestants trying to convince passersby to complete a series of predetermined tasks while unknowingly on camera.
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you have a deal, you have a date "When she suggested they go out for dinner, he said, ""You're on."""