Lucas Salik is a heart surgeon, renowned for performing bold experiments on other people's hearts. Ostensibly chilly, he harbours a secret obsession for his reckless and charismatic friend Hal. When Hal announces his intention to find a wife, Lucas is forced to carry out his most complex operation yet: to engineer the marriage, setting it on a perilous path to failure. But just as things appear to be working out, Lucas starts receiving ominous letters that threaten to jeopardize his intentions, his career - and his life.