Nine months shy of hs 40th birthday, freelance writer Tyler Harrison has started to experience horrific hallucinations. At first, he thinks it's just the stress of his job, but the hallucinations continue until they culminate at the three-day concert in Chicago, Lollapalloza, which he is covering for work. There he is approached by an older man who tells him that he's going to die on his fortieth birthday.
The man claims to be an angel named Matthew, and even though he gives Tyler enough evidence to convince him he's telling the truth, he doesn't know what to do with the information.
Tyler's underlying doubt and confusion about Paul's prediction turn to anger, both at God and those around him. As he begins to exhibit destructive behavior, he befriends Ellis, an internationally known DJ. Tyler is scared that he really is about to die. He's scared for his sanity. He's scared that if he does die, he's not going to Heaven. He also soon becomes scared of Ellis, who is wild and opens up a door of temptation to Tyler.
As Tyler begins falling in a downward spiral of fear and confusion, he reaches out to a pastor he met, Will, and tries to right his wrongs with some of the important people in his life in a desperate attempt to find peace before his 40th birthday.