Subject Seven is a young-adult novel by the American writer James A. Moore, first published in 2011 by Penguin.

Hunter Harrison wakes up and doesn't know where he is or who he is, but there is a tape telling him that he will get all of the answers he want as long as he listens to his kidnapper, Subject Seven.

The more I listened to the CD, the more I started liking the idea of a sort of “Jekyll and Hyde” scenario with military implications.

And after a few hours, I started thinking it would be a lot of fun to mess with character suffering from that sort of condition.

"[1] Jane Henriksen states that “the theme of this story isn't new,” but, “this updated version is uniquely appealing to teens.”[2] Publishers Weekly says “he nicely juggles the Jekyll and Hyde aspects of his characters,”[3] and John Peters added that "Dr. Jekyll and Mr. Hyde meet The Incredible Hulk,"[4] in this novel.

Publishers Weekly complemented it by calling it a "grisly mix of conspiracy novel and body horror fiction,” but says that there are, “usual plot holes associated with this type of genre.”[3] John noted that "readers patient enough to weather each team members protracted introduction will be rewarded.”[4] With “underlying themes,”[2] and its “violent and visceral storytelling,"[2] Jane added.