Robert Rath (Sylvester Stallone) is a paid assassin who wants to retire, haunted by the memory of murdering his own mentor Nicolai years ago. He is on an assignment when someone else gets to the 'mark' (target) before he does. That intruder turns out to be Miguel Bain (Antonio Banderas), a fellow assassin and a competitive sociopath. Bain plans to kill Rath to become the number one assassin.