Werner Herzog's latest madman to illuminate the screen obviously doesn't star his infamous collaborator, the late Klaus Kinski, or even the relatively more sedate Bad Lieutenant Nicolas Cage. Instead, Herzog's star is Michael Shannon, the Oscar nominee whose performance as a man recently released from a mental institution was the best thing about Revolutionary Road. In Revolutionary Road, Shannon's character John Givings tells Frank (Leonardo DiCaprio), "Plenty of people are on to the emptiness, but it takes real guts to see the hopelessness."
It's a familiar trope, using the mentally ill to "see" things that other characters are blind to, but in My Son Shannon's Brad McCullum grows more and more out of touch with reality until he believes God lives in his house, in a package of oatmeal.
My Son begins near the end. Two detectives (Willem Dafoe and Michael Peña) are on their way to a crime scene in a drowsy neighborhood of San Diego. On their way in, Detective Hank Havenhurst (Dafoe) is stopped by a neighbor holding a coffee cup, who amiably mumbles, "Razzle dazzle them. Razzle dazzle them," takes a sip from his cup (which reads "Razzle Dazzle"), and walks quietly away.
When they arrive, they find a dead body, the murder weapon nearby, and, strangely enough, the two witnesses still sitting in the chairs they were in when the murder occurred. They learn the suspect was the gangly neighbor with the coffee cup, and indeed, one of the witnesses says, "Brad McCullum. He did it. He stabbed her. Ever since he came back from from Peru, he's been strange. Well, not so much strange, as... different."