An imaginative, 11-year-old boy (Henry Thomas) discovers there's a sinister plot afoot to smuggle top-secret military information out of the United States inside a cassette of his favorite video game, Cloak and Dagger. Unable to convince his father (Dabney Coleman) that he's telling the truth about the enemy agents and the murder they've committed, the lad enlists help from his imaginary friend, a dashing spy named Jack Flack.