Twenty-four years after its initial publication, Caleb Carr’s novel The Alienist has finally made it to the small screen. It did not get there easily. In June 1993, before the novel was published, Paramount Pictures and producer Scott Rudin purchased the film rights for $500,000. Various screenwriters toiled away at various scripts, locations were scouted, and production was slated to start by the summer of 1995. But the book and its grisly contents were hard to adapt to the screen – at nearly 500 pages, truncating the story to an acceptable Hollywood running time proved impossible – and the adaptation never surfaced.

Almost a quarter-century later, TNT’s 10-episode adaptation, adapted by Hossein Amini and directed by Jakob Verbruggen, has arrived. Set in 1896, during New York City’s gilded age, the title refers to Dr Laszlo Kreisler, a criminal psychologist who works with the mentally ill or, in the 19th-century parlance of Carr’s novel, “those alienated from themselves”, their true nature.

When a 13-year-old boy is found disemboweled on the Williamsburg Bridge, his eyes gouged out and his genitalia mutilated, Kreisler is tasked by police commissioner Teddy Roosevelt with investigating the murder. He’ll soon find out that the boy, who’d been a prostitute at a brothel housing young men dressed up as women, is one of several victims, and the ruthless killer is on the loose.

All of this is taking place before the dawn of sophisticated forensic science (fingerprinting and the like) or any real understanding of and sympathy for mental illness, which makes watching the gradual inception of both play out on-screen novel and edifying. But save for its viscerally comprehensive production design (the show was filmed in Budapest) and its lavish attention to detail, The Alienist is, somehow, a bit of a snooze. Perhaps we’ve been spoiled by Hollywood’s cultish devotion to serial killer-centric entertainment, and even more so by all the shows about the mechanics of crime solving, but The Alienist lacks bite in a way it wouldn’t have a decade ago, when the idea of a limited series of this scope would have been unthinkable for most networks, let alone TNT.

The performances are solid across the board, especially that of German actor Daniel Brühl as Kreisler, an intrepid sleuth who, as another character puts it, “takes such pleasure in keeping everyone in the dark”. To society’s upper crust, his methods are strange, and the more he displays a persistent investigative resolve the more beguiled by the case(s) he becomes. “Only if I become him, if I cut the child’s throat myself, if I run my knife through the helpless body and pluck the innocent eyes from a horrified face, only then will I come to truly understand what I am,” Kreisler says, in a boilerplate speech that called to mind Jake Gyllenhaal’s “I need to look him in the eye” monologue as Robert Graysmith in Zodiac.

Luke Evans, as newspaper cartoonist John Moore, an old friend of Kreisler’s who teams up with him to solve the crime, is brooding if slightly miscast. And Dakota Fanning, rounding out the trio, plays the strong-willed secretary Sara Howard, the first woman ever employed by the city’s police force. Two of the best performances, though, are those of Matthew Shear and Douglas Smith as the brothers Isaacson, two bright and innovative Jewish forensic science specialists who stick out like sore thumbs in the very Irish-Catholic environs of Manhattan law enforcement.

Although The Alienist is surprisingly slow and dreary, Verbruggen – who has directed episodes of Black Mirror and House of Cards – has conducted some impressive world-building. In the seedy brothels and slums of New York, where Italian immigrants and sex workers live in terrible poverty, there’s a grey overcast to each and every shot that reflects an aesthete’s commitment to atmosphere and tone. Particularly striking are the slush puddles covering cobblestone streets, the tawny interiors and rusted stairwells.

In the polar opposite world of the very same city are Roosevelt and JP Morgan, who appear in an early scene at the opera, and a host of people who condescend to and devalue the victims of the killer’s heinous crimes. As did its source material, the show certainly has some interesting ideas about the era, its social stratification, and the elusive nature and provenance of evil. But, unfortunately, it delivers them with a certain dressed-up languor, emphasizing style over substance.

• The Alienist starts on TNT on 22 January and in the UK on Netflix on 19 April