The tipping point

'I am no saint, no martyr, no terrorist, no madman and no murderer ... I am a father. That's my story.' Dr David Evans, a top neurosurgeon at a hospital in Washington, faces the ultimate dilemma: if his next patient leaves the operating theatre alive, his daughter will die at the hands of a psychopath. He has 55 hours to save her. But Evans' patient is no ordinary man; he's the most important person in the US and what happens on the operating table may well change the course of history.