Fidelity
by Thomas Perry
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When Phil Kramer is shot dead in the middle of the night, his wife is left with an emptied bank account and a lot of questions. Jerry Hobart has some questions of his own. Now that he's been ordered to take out Kramer's widow, he figures there's a bigger secret at work--and a bigger payoff.

This part of the read so far has me wanting to go out and rent the book from my library. I can't wait to read on for the rest of the week. I like how it grasps you in right within the first few paragraphs.
I think I'm going to make a list of other books Mr. Perry has written and look into reading them also.