Smith and Jones - reformed outlaws Hannibal Heyes and Kid Curry - may have lost their shot at amnesty when a young woman identifies Heyes as the man who shot and killed a banker in a robbery. Heyes suspects a double, but they end up kidnapping the girl to prove their innocence.
The hoary "evil twin" story rears its ugly head again. If you're not tired of it, you'd probably enjoy the book more than I did.