The Duplicate, published in 1988, is a science fiction novel for young adults written by William Sleator.

[2] The main character, David, finds a device at the beach that can duplicate any living organism.

David ends up having to go to his grandmother's birthday after he loses a coin toss to the duplicate.

The book was praised by outlets including The New York Times,[3] the St. Petersburg Times,[4] and San Francisco Chronicle, which called the story "a singularly clear moment of horror intruding on daily life.

"[5] Kirkus Reviews also praised the book, though writing that the characters, particularly Angela, lacked dimension.