How can you prove your innocence when you can't remember the crime?

Being a cop runs in Billy Harney's family. The son of Chicago's Chief of Detectives whose twin sister, Patti, also followed in their father's footsteps, Billy would give up everything for the job - including his life.

After a brutal shooting, Billy is left for dead alongside his tempestuous former partner and an ambitious assistant district attorney. But somehow Billy survives - and is charged with double murder.

Billy remembers nothing about the shooting. Retracing his steps to find proof of his innocence, he discovers the existence of a little black book that he suspects contains the truth that will either set him free, or confirm his worst fears...