Yesterday's sins

Why would anyone put a bomb in the car of a retired USAF Major who writes cookery books and lives quietly with his wife?

Charlie Brodski has a past and it looks like it's catching up with him.

As an ex-bomber expert who defected to the Americans, he recognises the bomb attempt as the job of a professional.

When Charlie asks for help from the people who provided him with his new life and identity they ask him a favour.

It shouldn't be too hard, just to kill a middle-aged widower who's doing a placement prior to going to Rome to train for the Catholic priesthood.

Name of Costello, Jimmy Costello. A race against time begins. Can he get Costello before somebody gets him?