I have a friend who works in the mental health field. One time he told me (quite possibly in violation of every ethical oath he's taken) about a divorced father who kidnapped his kid because he was convinced his ex-wife had been replaced by an alien. As he was working on the case he realized that the move to commit this man to an institution flew in the face of watching a lifetime of movies. If it were Hollywood, the third act would reveal that he was right all along.
To my delight and surprise a similar bit of musing is one of the core concepts of Jay and Mark Duplass' remarkable 'Jeff, Who Lives At Home.'