The television police procedural is a genre, and like any genre, it makes an implicit contract with its audience.

Chiefly, that contract is about plot. Here's what you'll get, it says. Each episode, a crime will be committed, investigated with a certain amount of technical detail, and ultimately solved. That's it. We may introduce some embellishments — a chewy performance here, an out-of-left-field twist there, or maybe a tiny amount of character development — but week in and week out, we'll stick to the parameters.

There's something hypnotic about the dramatic rhythms of shows like Law & Order and CSI, as investigations proceed with a metronome-like regularity. It's a formula, and formulas rely on a set of mutually agreed-upon assumptions. When those assumptions get challenged, as in the infamous Law & Order episode "Aftershock," which took a set of characters that viewers had grown to see as plot devices and drilled down into their emotional lives, it can be off-putting. (No fair, show! That's not what I look to you for! I thought we had a deal!))

The pilot episode of Netflix's series Mindhunter, about the birth of the practice of profiling serial killers, hits its now-familiar story beats with exactly the metronomic and formulaic rhythm we've come to expect. There's fresh-faced, sensitive young FBI agent Holden Ford (Jonathan Groff). There's grizzled, seen-it-all FBI agent Bill Tench (Holt McCallany). There's their first meeting, when both begin to suspect that the bureau's old methods are ill-equipped to deal with a new kind of violent criminal (the series is set in 1977) whose actions cannot be mapped to clear, recognizable motivations.

It's a classic set-up. Add to it a supervisor (the excellent Cotter Smith) who can be depended upon to chew them out when their (sing along, you know the words) unorthodox methods attract the attention of higher-ups, and you've built a narrative engine that could keep chugging along, dutifully if unexceptionally, for several seasons: The X-Files, but for serial killers.

Now: That might not sound appealing, for any number of reasons. Maybe you don't share pop culture's enduring fascination with serial killers. Maybe you're specifically sick of seeing their crimes treated cavalierly, glibly, or, worst of all, in a manner that glorifies their deeds, and holds them up as genius breakers of societal norms. Or maybe you're just someone who finds the genre constraints of the police procedural predictable and dull.

I've talked to several people who fall into one or more of those categories (full disclosure: I fall into all of them); most of them decided to bail on Mindhunterafter the first episode, thinking they knew what was in store.

I told them, and I'm telling you: Keep going.

Despite its procedural trappings, Mindhunterproceeds in a curious, shaggy, sidelong way that defies the serial-killer-of-the-week formula promised by its pilot. Characterizations and relationships that seem paper-thin in that first episode incrementally deepen. A plotline involving an elementary school principal, and a case involving a death in Altoona, Pa. — both of which we've been conditioned to assume will be dispensed with quickly — keep confounding Ford, Tench, and us, in ways that reveal the limitations in their emerging forensic methodology.

It's that emerging, fits-and-starts methodology, and not serial killers, that's the show's true subject. The unorthodox and not entirely happy marriage of FBI procedure with academic psychology (Anna Torv's Dr. Wendy Carr brings a cool, intellectual energy to the proceedings) recalls the first few seasons of Masters of Sex, when the birth of a new social science faced suspicion and rejection.

Groff's portrayal of Ford as the world's softest, squarest Fed seems puzzling in early episodes — but it's there to allow him to lay the track necessary to take the character someplace. We witness his fascination with serial killers — revealed most clearly in a series of meetings with convicted killer Edmund Kemper (a chillingly matter-of-fact Cameron Britton). Crucially, however, his growing empathy is not held up (as it so often is, in facile pop-culture narratives) as something that offers him any particular insight. It's not good or noble or useful. It's a sign that the work is screwing him up.

Which is why what McCallany's doing, as Ford's partner Bill Tench, is so important to the series' success. On paper, it's less a role than a cliche — a grizzled walking crewcut, exasperated by his younger partner'sunorthodox methods.But McCallany modulates his performance so we see its shadings — he's frustrated by Ford, sure. But he's also clearly worried about him, as he should be.

Mindhunterdevotes much of its running time to the home lives of Ford and Tench and Carr, in a way that would break a conventional police procedural (or at least, in the case of that one Law & Order episode, inspire much head-scratching: I thought we had a deal, show!). But from the beginning — well: from the second episode, anyway — the series displays a willingness to dispense with the comforting and satisfyingly familiar story beats of the procedural genre if it means exposing something weirder, and truer — something less about the demands of the show's plot than it is about the messy, flawed and fumbling characters caught up in it.

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