THE DUPLICATE

When David observes a seagull inexplicably made into two gulls by a machine (labeled "Spee-Dee-Dupe") that he has found on the beach, it occurs to him that this may be a solution to his immediate problem: how to go simultaneously to his grandmother's birthday dinner and on his first date with Angela. Sure enough, the machine creates a duplicate David—who also claims to be the original. Sleator's premise is that the boys will do anything to keep their duality secret (they don't want to spend the rest of their lives as freaks), so they begin to negotiate elaborate plans to take turns at meals, school, and meetings with Angela. Enemies from the start (the duplicate seems to get the best of every bargain, including getting that first date), their enmity becomes more intense even as they cooperate in their increasingly difficult deception; suspense builds as David realizes that the duplicate is not identical to him but, rather, has a mad, vicious side that will dominate as he progresses to a speedy and inevitable end. There is a satisfying amount of action as David wages clandestine and finally overt war in an abandoned building, with Angela finally becoming an ally; and the question of whether David will be driven to kill before he is killed is mildly harrowing. Though Sleator's characters, especially Angela, lack dimension, his plot is developed with a terrifying logic that should keep the pages turning.