The most famous partnership in detective fiction started as a rent split.
In A Study in Scarlet (1887), Dr. John Watson comes home from Afghanistan with a wound, a thin army pension, and no family in England. An old acquaintance mentions a strange fellow at the hospital lab who has found some nice rooms but can’t afford them alone. The strange fellow looks up from his chemistry and says, “You have been in Afghanistan, I perceive.”And there it is.
Not destiny. Not a calling. A lease.
Every detective partnership needs something holding the two of them together. Something that keeps them in the same car, the same office, the same stakeout van at three in the morning when one of them won’t stop crunching sunflower seeds.
Over at The Pitch Master, I just wrapped a five-part series on best friend love in storytelling. One idea from that series turned out to unlock detective partners completely: A badge is glue to keep partners together.
Police partners and private detective partners get their glue from opposite places. Figure out which one you’re writing, and half your craft decisions make themselves.
Assigned: The Badge Is Free Glue
Police partners don’t choose each other. The lieutenant does.
That is a gift to writers. You never have to explain why these two are stuck together. The department did it for you, with paperwork. And because nobody asked either of them, conflict comes standard.
Lethal Weapon (1987) opens on Roger Murtaugh’s fiftieth birthday. His present from the LAPD is Martin Riggs, a grieving, suicidal loose cannon who the brass suspect is faking it for a psych pension. Murtaugh didn’t ask for him. Nobody would.
The X-Files went further. The FBI assigns Dana Scully to Fox Mulder’s basement office specifically to debunk him. Her original job is to file reports on why her partner is wrong. Every week, the believer and the skeptic stare at the same evidence and read it in opposite directions.
Tony Hillerman wrote Lt. Joe Leaphorn and Officer Jim Chee of the Navajo Tribal Police in separate books for years. When he finally put them on the same case in Skinwalkers (1986), he got a pairing built on a fault line: the older, logical lieutenant who has no patience for witchcraft talk, and the younger officer who is studying to become a traditional Navajo healer. Same reservation. Same murders. Completely different ways of seeing them.
Here’s the story question for assigned partners: Will they learn to trust each other?
The badge holds them together whether they like it or not. That means the friendship isn’t automatic. It has to be earned. And the moment readers wait for is the moment one of them chooses the other when the job no longer requires it.
Writing assigned partners
- Let them resent the assignment. Neither one picked this. Use it.
- Make trust the arc. Who backs up whom, and when does it cost something?
- Threaten the glue from outside. The department that put them together can split them up. A transfer request is a breakup scene with a form attached.
Chosen: The License Needs a Reason
A private detective doesn’t have a lieutenant. Nobody assigns a PI a partner.
That means if either one could walk away at any moment with no cost, your reader is going to wonder why they don’t. Chosen partners need a reason to stay in the car, and you have to put it on the page.
Let’s look at where some great private eye partnerships get their glue:
- The rent. Holmes and Watson, 221B Baker Street.
- The paycheck. Archie Goodwin works for Nero Wolfe. He lives in the brownstone, draws a salary, does the legwork Wolfe rarely leaves the house for, and needles his genius employer into taking cases so the bills get paid.
- The past. Patrick Kenzie and Angela Gennaro grew up together in Dorchester before Dennis Lehane made them partners. Shawn and Gus on Psych have been best friends since they were kids.
- A debt. Spenser and Hawk go back to their boxing days, and Robert B. Parker built their bond on old history and a trade of favors.
- A job that turned into something else. On Elementary, Joan Watson starts out as Sherlock’s sober companion, hired by his father. The paycheck brings her in. The partnership is what keeps her.
- Being a target. In The Nice Guys (2016), enforcer Jackson Healy is paid to scare private eye Holland March off a case. Then they both end up targets of the same people, and have to work together.
The story question for chosen partners is different: Why do they stay?
Every book has to renew that choice. If the reader stops believing it, the partnership reads hollow, like two characters sharing an office because the author needs them to.
Here’s the difference in two lines:
If they’re assigned, the story is about choosing each other anyway.
If they chose each other, the story is about what it costs to keep choosing.
A Tour of Detective Partnerships
Assigned or chosen tells you where the glue comes from. The kind of partnership tells you what the two of them do for each other. Here are five shapes that show up again and again, on the page and on screen.
1. The Genius and the Chronicler
Holmes and Watson. Nero Wolfe and Archie Goodwin. Hercule Poirot and Captain Hastings.
One partner is brilliant. The other tells the story. This is the oldest structure in the genre, and it does a sneaky job. The narrator can watch the genius work without ever being inside his head. You get to show every clue and hide the conclusion until the big reveal, and it all plays fair.
The danger is the chronicler who’s just furniture. Agatha Christie got tired of Hastings. In The Murder on the Links (1923), she married him off and shipped him to Argentina, and Poirot carried on mostly without him.
Compare Archie Goodwin. He’s funny, he’s capable, he’s a better detective than he lets on, and he has an opinion about his boss on every page. Readers come back as much for Archie’s voice as for Wolfe’s genius.
The takeaway: give your chronicler competence and an attitude. If your narrator only exists to say “Amazing!” he’s a mirror, not a partner.
2. The Veteran and the Rookie
Harry Bosch and Renée Ballard. Eve Dallas and Delia Peabody. Young Morse and Fred Thursday on Endeavour.
This is a mentorship, and the arc is built in: the rookie grows. In J.D. Robb’s In Death series, Peabody starts out as Eve’s uniformed aide, becomes her partner, earns her detective’s shield, and catches her first case as primary.
Michael Connelly paired Bosch, a retired LAPD detective with no patience for rules, with Ballard, a young detective exiled to the night shift with no patience for being sidelined. Two generations. One shared stubborn streak.
The takeaway: the payoff scene is the day the rookie is right and the veteran is wrong. Build toward it.
3. Equal and Opposite
Andy Dalziel and Peter Pascoe. Cagney and Lacey. Mulder and Scully.
This is the odd couple engine. Reginald Hill paired a big, crude Yorkshire superintendent with a university-educated young detective and got decades of novels out of the friction. Cagney & Lacey put an ambitious single woman and a married working mother in the same squad car.
Every time these two solve a problem, they want to solve it differently. You never have to import conflict. It’s already sitting in the passenger seat, complaining about the radio.
The takeaway: their differences have to show up in how they work the case, not just how they talk. Who wants to lean on the witness? Who wants to wait for the lab?
4. The Partner Who Does What You Won’t
Spenser and Hawk. Elvis Cole and Joe Pike. Easy Rawlins and Mouse.
This one is a private eye specialty. The detective has a code. The partner has fewer scruples and a lot more firepower.
Parker introduced Hawk in Promised Land on the other side of the case, as an enforcer for a loan shark. Robert Crais gave Elvis Cole a wisecracking voice and gave Joe Pike sunglasses and silence. Walter Mosley gave Easy Rawlins an old friend from Houston who will kill without blinking and grin while he does it.
The partner lets the hero keep his hands mostly clean. That’s the convenience. The interesting part is the price. Is the hero really clean if he keeps calling the guy who isn’t?
The takeaway: make your hero pay a moral price for the partner. That tension is what turns a bodyguard into a relationship.
5. The Badge and the Civilian
Castle and Beckett. Shawn Spencer and Detective Lassiter on Psych. Washington Poe and Tilly Bradshaw.
One partner has the authority. The other has a skill the system doesn’t. M.W. Craven pairs Poe, a bruising detective sergeant with the National Crime Agency, with Tilly, a sheltered civilian analyst who is brilliant with data and hopeless with people. He’s the access. She’s the insight. Neither one solves the case alone.
The takeaway: the civilian has to be useful, not lucky seeing what the cop can’t.
Which One Are You Writing?
Look at your detective and whoever is riding shotgun.
Who put them together, the department or the two of them? And what kind of partnership is it? Chronicler, mentor, mirror, muscle, or civilian?
Once you know where the glue comes from, you know your story question. Once you know the shape, you know what each one brings to the case.
Next time, we’ll look at what happens when the case closes and the partnership doesn’t, how detective partners carry a series, and ten ways to write a partnership readers will follow for sixty books.
TKZers, who’s your favorite detective duo? Are they assigned or chosen? And which of the five types would you put them in?
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