I am Number Four is a novel by Pattacus Lore from The Lorien Legacies about a teenage boy who is from another world. He is one of nine who came to earth after their world was destroyed by a race destined to kill. They kill in order. They have already killed the first three, and he is number four. He and his guardian, Henri, struggle to stay alive, and they are forced to change identities more than once on occasion.

At first, he is John Smith. As Smith and Henri go about their lives and try to finally live normally, their enemies have appeared once again. Is there time for him to hone his powers and save himself?

The book is great on details and gives so many better viewpoints than the movie. The author did very well and had a very good idea for this book.
This is the first book in a series of six.