In Agatha Christie’s The Clocks, Hercule Poirot solves the strange case of an unidentified dead man whose body is found in the home of a blind teacher named Millicent Pebmarsh. On the surface, the case appears to be quite complex, with strange clues and leads that don’t seem to go very far. When Poirot’s friend Colin Lamb brings him the case, though, Poirot’s first reaction is:

‘It must be a very simple crime.’

Lamb can’t understand why Poirot would say this and asks why it must be simple. Here is Poirot’s answer:

‘If it has necessarily to appear complex, it must be very simple.’

And so it turns out to be. Once Poirot finds out the truth, we see that the murder is, indeed, simple, and committed for a simple reason.

This isn’t the only fictional crime that’s a lot simpler than it appears to be. It’s one reason why investigators are taught the old medical maxim that ‘when you hear hoofbeats, think horses, not zebras.’ Of course, there are complex crimes committed for complex reasons. In a lot of cases, though, a crime is committed for a simple reason.

For instance, R. Austin Freeman’s The Mystery of 31 New Inn features a very odd medical case. Dr. Christopher Jervis is serving as locum for a colleague when he is summoned to the bedside of the very ill Mr. Graves. It’s a strange trip, as Jervis is transported in a closed carriage so that he doesn’t know where he’s going, nor why Mr. Graves’ housekeeper and butler seem so secretive. Still, he gives the required treatment and is transported back to his residence. He’s concerned there might be foul play involved, so he visits his friend, Dr. John Thorndyke, for advice. Thorndyke gives him a few suggestions, but Jervis gets busy with other cases and doesn’t think about Mr. Graves until a few weeks later when he is summoned again, under the same strange circumstances. Something is definitely not right, and Jervis and Thorndyke work together to find out what’s going on. They find that this case is simpler than it seems, and that it’s connected to another case Thorndyke is working – a case of a will that was changed for seemingly no reason.

Bill Crider’s Too Late to Die is his first Sheriff Dan Rhodes novel. In it, Rhodes is alerted when the body of Jeanne Clinton is found in her home. The first and most likely suspect is the victim’s husband, Elmer. He could have had a motive, too, as Jeanne was ‘a bit wild’ before she was married. But Elmer Clinton says he was at work at the time of the murder, and he can prove it. So, Rhodes has to look elsewhere for the criminal, and it’s not long before he discovers more than one person with a motive. It has the makings of a complicated case that’ll involve untangling several alibis. In the end, though, the case is simpler than it seems on the surface.

Kevin Wilson’s Now is Not the Time to Panic takes place in the summer of 1996, in the small town of Coalfield, Tennessee. Sixteen-year-old Frances ‘Frankie’ Budge is a budding writer who’s feeling a bit at loose ends, not sure what she’s going to do with her summer. Then, she happens to meet Zeke Brown, a gifted artist who’s staying in town for the summer. The two strike up a friendship, and together, create a unique poster that reflects both of their talents. They decide to copy and post their creation in different places in town. It’s a simple game – to see what happens when they put up their poster. But it soon spins into something more complex when people notice the posters and wonder about them. All sorts of explanations (including alien activity and Satanism) start being offered; meanwhile, Frankie and Zeke remain quiet about their role. The whole thing snowballs into what is later known as the Great Coalfield Panic of 1996, and it leads to tragedy. Twenty years later, Frankie is a successful writer. When a journalist doing a story on the panic contacts her, Frankie will have to decide how much, if anything, she’s going to tell about the simple explanation for what happened.

And then there’s Sarah Woodbury’s Crouchback, which takes place in 1284 Wales. King Edward of England and Queen Eleanor are staying in a Welsh castle as they await the birth of the baby who will grow up to be Edward II. One of the queen’s ladies in waiting is Lady Catrin, a widow who is Welsh, but spent the last decades in English. She gets drawn into a murder mystery when a man’s body is discovered in a disused barn. Near the body is a set of strange symbols. The dead man was wearing the tunic of Lady Catrin’s husband, so she is asked to identify the body. Rhys, the coroner’s assistant who is investigating the murder, has known Catrin since they were children. He is certain she’s not guilty, but he believes she may be useful in finding out who the killer is. Then, there’s another murder. And another. In each case, strange symbols are left behind. It looks like a very complicated case on the surface. But the reality is, it’s much simpler than it seems.

There are certainly cases (both real and fictional) that are extremely complex and involve several tangled threads. But there are also plenty of cases that have a very simple, ‘horses not zebras’ explanation. Which ones have stayed with you?

*NOTE: The title of this post is a line from the Eagles’ I Can’t Tell You Why.