Mr Murder is an amazing story - starting from a personality who has no past and no identity, that is driven by forces he cannot identify and who he cannot appeal to for help, driven from assignment to killing assignment with no idea why he is what he is and is doing what he is doing - leading the most tortured and meaningless existence - he decides he wants A LIFE, he wants a FAMILY, he wants A HOME. And he is going to take it.
From the imposter that looks exactly like him. Take his family back - his wife and two daughters - and show them what a real father is like.
Problem is, his only experience of family life is through movies, including the secret stash of some senator he had to kill which he watched avidly in the aftermath - adults with children - children with children. He knew what a family should be. He would teach them.

Dean Koontz at his best.