The visitor

Sergeant Amy Callan and Lieutenant Caroline Cooke have a lot in common. Both were army high-flyers. Both were aquainted with Jack Reacher. Both were forced to resign from the service. Now they're both dead. Found in their own homes, naked, in a bath full of paint. Apparent victims of an army man. A loner, a smart guy with a score to settle, a ruthless vigilante. A man just like Jack Reacher.