Sweet Vengeance (Mission Belles #3)
Pamela Gibson

Sean Mitchell, former spy and now successful horse trainer, is baffled by his sister’s disappearance. When the seductive and dangerous Elena Santoro turns up and offers to help him, he’s cautious. Can he trust a woman whose brother was once his enemy?
As the chaos brought on by the gold rush unfolds in San Francisco, Elena and Sean fight to elude an enemy who is frantic to find Sean’s sister before they do. But the greater danger lies in their growing affection for each other, an affection tempered by the ghost that will always be between them.