There is a long and robust literary tradition of the crime-solving duo. Holmes and Watson. Nick and Nora Charles. Nero Wolfe and Archie Goodwin. Peter Wimsey and Harriet Vane. As a writer it’s nice to have two protagonists, if for no other reason than to have them discuss the plot together. It works particularly well if one is smarter than their sidekick and gets to explain how all the pieces fit together.
But what about the criminal duo? Where’s Moriarty’s partner? The truth is, villainous pairs, although not unheard of, are comparatively rare. I was fairly young and very impressionable when I saw Alfred Hitchcock’s Rope on television, a film that opens with two young men murdering an acquaintance together, then hiding the body in a chest while hosting a cocktail party. Maybe it was Rope that began my fascination with the idea that two people acting together might be deadlier than one.
In my new novel, The Kind Worth Saving, two teenagers – a popular extrovert named Joan and a bookish introvert named Richard – meet at a resort hotel in Maine. In normal circumstances they would never be friends, but they are marooned together in a place populated with grownups and they form a relationship that turns out to be deadly.
The following are some of my favourite murderous duos in fiction.
1. Evil Under the Sun by Agatha Christie (1941)
There are a few murderous pairs flitting around in the Agatha Christie universe. Without giving too much away about this particular book, Poirot is on holiday in Devon, which means that someone in his orbit will die. I love Christie for many reasons but one of them is her elaborately planned murders, well displayed here. And the thing about elaborate plans is that they are easier to pull off if one has a partner.
2. Double Indemnity by James M Cain (1943)
Probably the most familiar trope of the criminal duo is the adulterous couple plotting the death of one of their spouses. No book does it better than Double Indemnity. Walter Huff and Phyllis Nirdlinger are not exactly pillars of saintliness when they meet, but once together their lust and greed propel them towards a plan to murder Phyllis’s husband. The ending of this novel is Cain at his best – bleak, cynical but all too human.
3. Compulsion by Meyer Levin (1956)
A thinly veiled retelling of the real-life Leopold and Loeb story, which was also the basis of Patrick Hamilton’s play Rope, filmed by Hitchcock. In this novel, Judd Steiner and Artie Strauss are the stand-ins for Nathan Leopold and Richard Loeb. Levin’s book is a psychologically astute account of how two upper-class college students in the 1920s, inspired by Nietzsche’s writings on the Übermensch, turn their fantasies of intellectual superiority into the premeditated murder of a young boy.
4. The Getaway by Jim Thompson (1958)
Doc is a career criminal specialising in bank heists. His partner in crime is his wife Carol, and as you might gather from the title, most of this book centres on Doc and Carol’s attempt to evade capture and make it to Mexico, following a bank heist. Like all of Thompson’s books this one features a rogue’s gallery of sleazy cops and robbers; an almost dystopian vision of mid-century America. And if you’re only familiar with this story from its two film adaptations, take note that neither of those movies delve into the surreal final third of the novel in which Doc and Carol find themselves in a retirement community for criminals.
5. The Boy Who Followed Ripley by Patricia Highsmith (1980)
The fourth of five novels that comprise Highsmith’s “Ripliad”, all following Tom Ripley, an American art forger and sometime murderer living in Europe. Highsmith often returned to the theme of doubles, and to exploring what happens when sociopaths befriend one another. Here, Ripley meets a young man who confesses to him that he has killed his own father. A strange friendship ensues (friendships in Highsmith novels tend to be strange), partly because Ripley sees himself in the boy. An odd book but psychologically fascinating; the question Highsmith asks seems to be whether two people with no real empathy can form a true bond.
6. Killshot by Elmore Leonard (1989)
There are numerous criminal partnerships in Leonard’s novels, probably because Leonard loved writing dialogue and it takes two to talk. He also loved writing less-than-brilliant criminals, especially ones with high opinions of themselves. Richie Nix is just such a character, a motormouth hitman tasked with killing a married couple in the witness protection programme. Richie’s partner is Blackbird, who is as calm as Richie is hyper. Their scenes together, especially their dialogue, propel this funny, scary book.
7. The Bridesmaid by Ruth Rendell (1989)
Along with Highsmith, Rendell is the master of the psychological thriller. While skilled at writing more traditional whodunnits, she excels at twisted individuals. In this dark morality tale, two damaged souls meet at a wedding and begin an obsessive relationship. Phillip is obsessed with beauty and disgusted by violence, and Senta is a fantasist divorced from reality. The story really begins when Senta suggests they both commit a murder to prove their love.
8. A Walk Among the Tombstones by Lawrence Block (1992)
Block’s series of books about Matthew Scudder, an alcoholic unlicensed detective in New York City, are some of the best crime novels still being written. Block does everything well but he really shines in creating terrifying villains. And the duo from this novel, the 10th in the series, are particularly horrific. This is a highly grisly, highly suspenseful book about what might happen when two psychopaths feed off one another.
9. A Simple Plan by Scott Smith (1993)
Three men in Ohio, two of whom are brothers, find a crashed plane in the woods that contains a dead pilot and $4m. They agree on a plan for splitting the money, but not surprisingly, that plan starts to go spectacularly wrong. The criminal duo in this book, as I see it, are Hank, one of the brothers who find the plane, and Sarah, his wife. Twisted by the possibility of so much money, and goaded along by each other, Sarah and Henry become a Midwest version of the Macbeths at their worst.
10. The Devil All the Time by Donald Ray Pollock (2011)
I read a lot of crime fiction, which means I also forget a lot of crime fiction. But I don’t think I’ll ever forget Carl and Sandy Henderson, the two serial killers that are part of the tapestry of dead-end lives in Pollock’s dazzling and disturbing 1950s-set debut novel. Carl is a photographer who uses his wife to lure men (mostly drifters and hitchhikers) to their doom along the road. He calls his victims “models”, posing them in horrifying tableaux before and after their deaths. It’s a symbiotic relationship in the worst possible way.
• The Kind Worth Saving by Peter Swanson is published by Faber. To help the Guardian and Observer, order your copy from guardianbookshop.com. Delivery charges may apply.
