Timeline is a science fiction novel by Michael Crichton that was published in November 1999. It tells the story of historians who travel to the Middle Ages to save a friend of theirs who already traveled back in time before them. The book follows in Crichton’s long history of combining technical details and action in his books, addressing quantum physics and time travel.
The novel spawned Timeline Computer Entertainment, a computer game developer that created the Timeline PC game published by Eidos Interactive in 2000. A movie called Timeline based on the book was released in 2003.