Being involved in a murder investigation is stressful whether one's a witness, a suspect, someone in the victim's family or the detective. One reaction to stress is increased adrenaline, the very same adrenaline that helps to fuel that "rush" we feel during the first stages of a love affair. So it's no surprise to see how many crime novels include romantic sub-plots or at the very least, strong attraction. And it's not just the adrenaline. The reality of how horrible murder is can leave a person lonely, frightened and vulnerable. That, too, can trigger attraction. So can the need for comfort that comes from being exposed to the stark reality of murder. When it's done well, that "sizzle" can add a layer of interest to a novel or series. On the other hand, it's very tricky because that "sizzle" can also easily become cloying and contrived. What's more, the whole point - the focus - of a well-written crime novel is the crime and its detection. Anything that takes away from that plot also takes away from the quality of the novel.
Several of Agatha Christie's novels include those dashes of attraction. For instance, in The Mystery of the Blue Train, we meet Katherine Grey. For ten years, she's been companion to Mrs. Hartfield. When Mrs. Hartfield dies, Katherine finds out to her great surprise that she's inherited her employer's considerable fortune. One of Katherine's first decisions is that she'll use some of her inheritance to travel; her first stop will be Nice, where her distant cousin Lady Rosalie Tamplin lives. She books a ticket on the famous Blue Train and soon gets involved in a murder investigation when Ruth Van Aldin Kettering, who's traveling on the same train, is strangled. Hercule Poirot, too, is traveling by that train and is hired by Ruth's father Rufus Van Aldin to find her murderer. Katherine Grey's involvement in the investigation puts her into contact with two very different men: Major Richard Knighton, Van Aldin's secretary; and Derek Kettering, the victim's husband. Both men are attracted to Katherine and although that sub-plot doesn't take center stage in the novel, it's a clear example of how that "rush" of adrenaline can lead to attraction.
A similar thing happens to Lucy Eyelesbarrow, whom we meet in Christie's 4:50 From Paddington (AKA What Mrs. McGillicuddy Saw!). Lucy is a professional housekeeper with an excellent reputation and a long list of clients. She's educated, contented in what she's doing, and certainly not looking to become attracted to someone. But things change when Miss Marple persuades her to take a job at Rutherford Hall, the home of the Crackenthorpe family. Miss Marple needs Lucy's help to solve a murder that a friend of Miss Marple's actually witnessed. The murder was committed on a train, and the only place the body could logically be is on the property of Rutherford Hall, so Miss Marple enlists Lucy to find the body. Lucy takes up her duties at the Crackenthorpe home and before long she finds the body of an unidentified woman - the same woman who was murdered on the train. Inspector Bacon and later, Scotland Yard detective Dermot Craddock, investigate the murder and with Miss Marple's help, find out who the woman was and who killed her. In the course of her work at Rutherford Hall, Lucy finds herself attracted to two men. One is Cedric Crackenthorpe son of the family patriarch. Cedric's an artist who lives on the island of Iviza and was visiting the family home during the Christmas holidays when the murder was committed. The other is Bryan Eastley, son-in-law of the family patriarch. A widower, he's a war hero who's looking for a way to fit into post-war society. Both men are very much attracted to Lucy, too, and their interactions form an interesting sub-plot to this novel.
Some of Dorothy Sayers' novels treat the same theme. In Clouds of Witness, for instance, Lord Peter Wimsey sets out to clear the name of his brother Gerald, Duke of Denver. The Duke's been charged with murdering Denis Cathcart, his sister Mary's fiancé. Wimsey and Inspector Charles Parker investigate the death and slowly unravel the complicated series of events that led up to Cathcart's death. Along the way, Parker and Mary Wimsey become attracted to each other, much to the Duke's discomfiture. Their relationship develops though, and in Strong Poison, we learn that they're planning a future together. Wimsey himself falls prey, you might say, in Strong Poison when he meets mystery novelist Harriet Vane, who's on trial for murdering her former lover Philip Boyes. Wimsey, who's attending the trial, falls in love with Vane and wants to clear her name so that he can marry her. With some help from several friends, he finds out who really killed Boyes and why, and at the end of the novel, he makes it very clear that he wants to marry Harriet Vane. For her part, Harriet's wary of a romance that starts under those conditions, so it's quite a while before she allows herself to fall in love with Wimsey.
Wimsey isn't the only susceptible sleuth, either. In Tony Hillerman's Skinwalkers, Navajo Tribal Police officer Jim Chee has arrested Roosevelt Bistie on the suspicion he murdered Dugai Endocheeney, who was found stabbed to death near his hogan. Bistie has been granted legal representation through Dinebeiina Nahiilna be Agaditahe (DNA), the Navajo Nation legal services program. At first, Bistie's representative Janet Pete is very much at odds with Chee, whom she sees as part of the system that's "railroading" her client. Over the course of this novel and several subsequent novels, though, she and Chee get to know each other better and find themselves drawn to each other. Their relationship doesn't end up being permanent, but we see how powerful the "adrenaline rush" of attraction can be. Interestingly enough, Hillerman doesn't make the evolution of this relationship a major focus of the novels that feature Janet Pete; instead, this relationship is woven through those novels as a sub-plot.
The same thing is true of the relationship between Stephen J. Cannell's L.A.P.D. cop Shane Scully and Internal Affairs investigator Alexa Hamilton. When they first meet in The Tin Collectors, Hamilton is pursuing a case against Scully, who's been accused of inappropriate use of a weapon, among other things, in the death of fellow officer Ray Molar. As it turns out, Scully's being "railroaded" by a group of powerful people, among them top L.A.P.D. administrators. When Scully finally convinces Hamilton that he isn't guilty, the two work together to clear Scully's name and to expose the corruption in the Department and in the City that led to Scully's arrest. During the course of this novel, Scully and Hamilton go from mistrust and contempt to respect for and attraction to each other. In later Shane Scully novels, the two build a life together.
Michael Connelly's Harry Bosch meets more than one of his romantic partners during the course of his investigations. For instance, in The Black Ice, he meets Sylvia Moore while he's investigating the death of her husband Calexico "Cal" Moore, a fellow L.A.P.D. officer. Moore apparently committed suicide, but the forensic evidence strongly suggests that he was murdered. So Bosch decides to find out what really happened. In the course of this investigation, he gets to know Moore's widow and the two find they have much in common. They begin a relationship and although it doesn't last (this is Harry Bosch, after all ;-) ), it's interesting to see how the adrenaline "surge" of the investigation and of dealing with Moore's death draws the two together. You might say a similar thing of Bosch's relationships with former FBI agent Eleanor Wish and FBI agent Rachel Walling, both of whom he meets in the course of investigations.
And then there's the relationship between Peter Robinson's DI Alan Banks and Sergeant Annie Cabot, whom Banks meets in In a Dry Season. In that novel, the two work together to solve the murder of a woman whose skeleton is found in the once-buried Yorkshire village of Hobbs End. Banks' marriage has broken up, and with his vulnerability, as well as the stress of this case, it's not surprising that he and Cabot are drawn to each other. Their relationship has its ups and downs, but it's a solid example of the way the adrenaline and stress of an investigation can draw people to each other.
It's not surprising in real life or in crime fiction when the circumstances of an investigation draw people together. So long as it happens naturally, as a part of the plot, and doesn't take the focus away from the plot, those "sparks" can add a layer of interest to a story. What's your view?
*NOTE: The title of this post is a line from the Eagles' Life in the Fast Lane.