In the Book
In the Movie
Gray Grantham is Caucasian
Gray Grantham is African-American
The film does not contain the murder of Matthew Barr and therefore does not show the primary antagonist, Victor Mattiece.
There is more dialogue by Khamel in the book, as he arrives on shore and meets a man who gives him a ride into the city. The man talks about knowing this is the terrorist, but not wanting to look at him because of that. Eventually he does look at Khamel, who kills him for it.
The villains continue their hot pursuit as Darby Shaw opens the safe-deposit box, putting a bomb in Gray Grantham's car and shooting at both in the parking garage in the film but not in the book
In the book Thomas seems to be attempting to be sober, where in the film his alcoholism is alive and well as he dates Darby.