A Shock to the System (1990) starring Michael Caine is an adaptation of the novel by Simon Brett, published in 1984. What makes this adaptation particularly interesting, is how the main character has to change for the two different endings to work. At the end of the novel, Graham Marshall is about to be arrested for three murders; a homeless man, his wife, and his new boss. At the end of the movie, he gets away with those three murders and the murder of a company executive. Graham Marshall’s transition is from a completely despicable character, to a likeable scoundrel.

For the first murder, Graham is approached by a homeless man. Graham has just been passed over for a promotion and he’s now answering to a younger man he hates. In the novel he acts out of pure rage, so even though he doesn’t intend to kill the man, he has no justification for his actions. In the movie the homeless man threatens him, so when he pushes him onto the subway tracks, at least he’s acting in self-defence.

The second victim is his wife. In both the novel and the movie it’s a matter of using his wife’s death to pay off the mortgage. What distinguishes the two, is in the novel they have two children, and he’s happy to send them to live with his sister-in-law and be rid of them. The fact he doesn’t love his own children makes the reader despise him. In the movie they have two dogs. He doesn’t keep the dogs, but it doesn’t produce the same emotional reaction.

The third victim is a younger executive that gets promoted instead of Graham. In both the novel and the movie he pretends to be interested romantically with a younger woman in office, then drugs her. His plan is that she’ll think he’s been in her apartment all night, providing him with an alibi. While she’s unconscious, he leaves the apartment and rigs the propane tank in a yacht belonging to his new boss. In both cases you’re disgusted by his behaviour, using someone who admires him in order to commit murder. Graham’s new boss isn’t described positively in the novel, but he’s portrayed as extremely arrogant and condescending on screen. It doesn’t justify Graham’s actions, but it’s easier to understand why Graham hates him enough to want to kill him.

At the end of the novel, you’re glad that Graham Marshall is going to finally face justice. At the end of the movie, when it’s clear he’s just killed an executive because he wants his corner office, you laugh. From a writer’s point of view, it’s interesting to note how subtle changes influence how the audience reacts to a character. And when it comes to portraying a likeable scoundrel, no one is better suited for the role than Michael Caine.

Copyright © 2021 by J. Paul Cooper

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