[This is the inaugural episode of Armchair Detective, a C4 column about reading mysteries. This time: how passion can make or break a mystery. Follow this column here.]

Relatively late in my reading career, I came to the decision that I shouldn’t try to finish bad books, because they sour me on reading and waste my time. Mysteries are a bit different because they naturally reward a finished read, and I think there’s value (and fun to be had) in deconstructing what makes the bad ones bad. If I’m going to quit on a mystery novel, it’s probably dead middle of the road: not bad, per se, but certainly not good. Just, kinda, average.

Last week, I had to quit on not one, but two mystery novels—If the Dead Rise Not, by Philip Kerr, and The Man from Beijing, by Henning Mankell—both of which looked and felt much better than average. At first, I couldn’t quite figure out the problems I had with them—when I finally did, I found that it was one problem with two sides. These two novels and their complementary shortcomings illustrate a crucial, but subtle, element of good mystery narrative.

I started reading If the Dead Rise Not first, after I heard a glowing review on Fresh Air, and it sounded terrific. Dead has a great hook: it’s set in pre-WWII Nazi Germany, when Hitler’s crimes are just beginning, but there’s already no justice in Berlin for Jews. It stars Bernie Gunther, who was forced out of the police for not being a Nazi, and, though he’s been reduced to a hotel detective, he’s the only one willing to dig into the shadows.

Kerr uses oppression and injustice to light Gunther up with righteous rage, but he doesn’t give Gunther anywhere to go, and we’re left with a human flamethrower, spouting fire impotently into the air.

To make matters more confusing, Kerr writes with such obsessive historical accuracy that his jokes and references seem inscrutable for anyone who didn’t actually live in 1930s Berlin (for example, an off-the-cuff, unexplained Alfred Döblin mention… who?).

Beyond that, the language itself is confusing. Everybody’s speaking German, but Gunther often uses English idioms, and a mysterious American’s German comes through in perfect (and 1930s-sounding) American English. Like this, one of his lines:

“God damn it, Behlert, what kind of flea circus are you chumps running here, anyway? Jesus Christ, if this is Berlin’s best hotel, then I’d hate to see the worst.”

A couple hundred pages later—about a third of the way through—Bernie solved his case. Wait, what?

I remembered the body that had washed up in the river, which seemed to be the primary investigation, and Gunther was looking into that other case as a favor to that police detective—was that the same crime? Then there was the mystery of the missing lacquer box, and the weird, suspicious American. Through all these minor investigations, Gunther was a hard-charging bulldog, but he didn’t seem to be getting anywhere.

When I stopped, I still wasn’t halfway finished and I’d been reading Dead for nearly a week. I wasn’t enjoying myself very much, and it was slow going. What seemed to be the main case—the washed-up body—turns out to be an accident, not even a homicide. Gunther’s left bellowing at nothing, and his passion fizzles (along with my interest).

By then, I was also reading The Man From Beijing. I’d put it down for a few days to focus on Dead, and then after I quit Dead, I had trouble remembering the plot of Beijing as well. The difference was that Beijing reminded me in less than a page: 19 people are slaughtered in a tiny Swedish town one night, nearly the whole population. That’s the case, and it’s big and memorable.

I gave Beijing up, too, after a single day. I didn’t even make it to the Beijing man.

I gave it up because I hated waiting around, watching a clutch of lifeless, indistinguishable detectives flatly suss out the logical ramifications of 19 brutal murders:

“Is there a risk that this maniac, if that’s what he is, might strike again?”

“Yes,” said Sundberg. “As we know nothing at all, we have to assume that anything might happen.”

“There’s going to be panic out there,” said Lonngren. “For once I’m relieved to live in town.”

I don’t care for droll-voiced Swedish crime books (cf: Larsson, Stieg), and I don’t care for bored coppers.

Dead and Beijing each have half the recipe for a great mystery, and each are lacking the other’s half. Dead has an emotional, unstoppable detective with righteous fire in his belly, but it lacks a case big enough for him to sink his teeth into. Beijing has a huge case, but its protagonist(s) wouldn’t much care if they were reassigned to the pawn shop squad the next day.

Great mysteries are defined by the emotion they create. That emotion comes from a protagonist who cares deeply and uncontrollably, but it has to funnel into the solving of an important case, a case so important that it wrenches even more spirit and energy from the hero, it requires so much of him that it threatens to destroy him. That case doesn’t need to be headline-catching, or world famous, as long as its key turns his lock.

The most suspenseful, most passionate mystery I’ve read this year is The Last Child. In it, a young boy tirelessly searches for his sister, who’s been missing for a year. The detective from the case still visits the family, and still feels guilty for never finding the sister. These are autocratic characters with independent power sources; they are driven.

Then, as the boy and the cop search for answers, the case unfolds in twists and risks. It’s dangerous and difficult and it perpetually demands more and more from both of them. This case isn’t 19 bodies and a serial killer, but it is crucially important to both leads. Child is irreducible: take out any part of this machine and it will crumble.

Without that codependent recipe for passion, you might get a great character, or a great case, but you won’t get a great mystery.

Good recent mysteries: Noir, by Robert Coover, and Misadventure, by Millard Kaufman. These are the exceptions that prove the rule. Neither have the passion (or deliver the suspense) of The Last Child, but both feature phenomenal writing and superb entertainment.

Reading now: The Case of the Man Who Died Laughing, by Tarquin Hall