The alternative way of describing Janet Jackson and Justin Timerlake's Superbowl 2004 antics. See also "wardrobe malfunction." Costume reveal is perhaps more honest given that it was clear they intended the "reveal," but "wardrobe malfunction" is more fun to use (e.g., "My date last night was terrible - I think he had a wardrobe malfunction").
When Jason was jumping on the trampoline, he wasn't wearing anything other than a speedo, and his business was completely showing. Talk about a costume reveal!