Dr. Jason Cole is a highly respected neurosurgeon who appears to have it all – but also harbors a deep, dark secret. Every night at the same hour, something inside Jason changes, leaving him almost unrecognizable – seductive, devious, borderline sociopathic. This new man is his dangerous alternate personality who goes by the name of ‘Ian Price.' For years he's kept him in check with a powerful experimental sedative. But now his – their – body has developed a resistance to the serum, setting Ian free once again. And to make matters worse, after being suppressed for so long, Ian is hell-bent on taking revenge on his oppressor. With everyone Jason cares about at risk, he must stop Ian once and for all. Will they find some common ground, or will they bring each other down?