No doubt the budget for “The Limehouse Golem” was but a pittance of the monetary muscle behind “IT,” that OTHER scary movie debuting this weekend, but this nasty little Victorian London horror film has more than a few blood-soaked charms of its own.

Based on a novel by Peter Ackroyd and directed with style by Juan Carlos Medina (with an effectively sharp script from “Kick-Ass” scribe Jane Goldman), “The Limehouse Golem” benefits greatly from two terrific performances: the invaluable and ever-dry Bill Nighy as a Scotland Yard detective, and Douglas Booth as a cross-dressing, music hall performer of considerable note (so to speak) who might just hold the key to a series of grisly murders terrorizing the city of London.

This is one of those historical scary movies combining real-life events and people with fictional scenes and wholly invented characters.

Booth’s character of Dan Leno is based on a real-life music hall singer and comedian who achieved some success but later went mad. George Gissing (played by Morgan Watkins) was an actual writer of the time.

Will it matter if you know which portions are true and which are pure fiction? Nah. The sure bet is virtually nothing we see here transpired in this manner in the London of 1880 (or in the flashback sequences). The Limehouse Golem murders, while obviously influenced in some measure by the Jack the Ripper case, are pure fiction. So let’s get on with it.

Nighy plays Inspector John Kildare, who is in the latter stages of a career best described as spotty. Kildare has been assigned to the Limehouse Golem murders — but only after a number of more distinguished investigators have failed to solve the Ripper-like series of killings. Kildare has been handed the case so he can become the fall guy when the murders remain unsolved. He is aware of this, but it does not deter him from trying to figure out this unholy mess.

(“Limehouse” refers to a notorious district in Victorian London rife with crime and poverty. The Golem is an often frightening creature from Jewish folklore.)

When the failed writer John Cree (Sam Reid) is found dead, suspicion immediately falls to his wife Elizabeth (Olivia Cooke). But while investigating that crime, Kildare begins to wonder if the murder of John Cree is actually the work of …

The Limehouse Golem!

In flashback sequences, we learn about the background of Elizabeth, once known as the music hall singer “Little Lizzie.” We’re introduced to Dan Leno, who achieved his greatest fame in cross-dressing parts. And we meet any number of colorful characters, including a friendly stage manager (Eddie Marsan from “Ray Donovan”) and a horny little person (Graham Hughes).

Meanwhile, in present day — that is to say, 1880 London — Kildare’s investigation becomes increasingly complex (and sometimes hard to follow), as he begins to wonder if the victim John Cree himself could have been the Limehouse Golem. But there are a number of other suspects, including Karl Marx (Henry Goodman) — yes, THAT Karl Marx.

Nighy leaves behind his trick box of winks and sly smiles and sarcasm for a relatively straightforward performance, and wisely so. As outlandish as the material can get in “The Limehouse Golem,” this is serious stuff. (The film is dedicated to the late Alan Rickman, originally cast as Inspector Kildare.)

Set design, costumes and production values are all first-rate, befitting a film of much larger scope.

★★★

RLJ Entertainment presents a film directed by Juan Carlos Medina and written by Jane Goldman, based on the novel “Dan Leno and the Limehouse Golem” by Peter Ackroyd. No MPAA rating. Running time: 105 minutes. Now showing at AMC Woodridge and on demand.