Nancy's in Chicago to cheer for the Emerson College basketball team—led by cocaptain Ned Nickerson—against their rivals. But she can't believe her eyes. Has Ned saved his sickest moves for the post-game celebration? Is he really making a pass at Denise Mason, a cheerleader who bears a striking resemblance to Nancy?

The mystery takes an even more serious twist when a kidnapper, intending to abduct Denise, grabs Nancy instead! Denise's father is the curator of a museum, and a team of art smugglers is making a play for a priceless painting. In this case of forgery and mistaken identity, Nancy discovers that deception and danger are the only rules of the game.