Abraham Lincoln Didn't Sleep Here — Tom Haikin

A rich corporate executive has hired Todd and Molly to look into the past of a young man who is becoming serious about his daughter. Their initial check turns up nothing to report and that's what bothers the detectives. Could it be that Abraham Steven Lincoln is too clean? The detectives begin to wonder if Steve is a Secret Agent, in Witness Protection, or a very clever identity thief. It will take a couple of trips to a small town in Montana for them to solve the mystery. This is the third novel in the Todd Dugan mystery series.