Deadwood is part of a double-novel paperback published by St. Martin's Press. The other story is Manhunter, both by Max Braun.
Private detective Luke Starbuck is on the trail hunting for an accused killer, Mike Cassidy. Starbuck was hired by William Dexter on behalf of a mysterious mine owner in Montana to locate and kill Cassidy. He finds out that Cassidy is holed up in the Hole in the Wall, Wyoming, and he puts on a disguise and finds Cassidy there after an attempt or two on his life. Luke is over-powered by Cassidy and his young friend who turns out to be Butch Cassidy - no relation. Mike beats the tar out of him trying to find out who he is and what he's after and almost kills him while Butch holds a gun on him.
After recuperating, they become friends and decide the character they want is the person who hired Dexter. Luke finds out that the attempts on his life are related to a man he killed earlier, Dutch John Henry. He heads off to find out everything he can about Dutch John, and ends up in Deadwood, where this mysterious Ira Lloyd, owner of the Grubstake Mining Company and the man who hired Dexter, makes his headquarters. Luke continues on to settle the case in an exciting and dangerous way.
I really enjoyed reading Deadwood and the surprise ending. I give it five stars for action and suspense and look forward to reading Manhunter, another Starbuck story.