Jussi Vares (Antti Reini) is approached by Olle (Markku Maalismaa), a pastor from small village in the hinterland, who wants him to solve a crime that the police seem to have given up on. Just for a change, it’s about the murder of a sexy young girl, and there is a long list of potential suspects. Could it be Taisto Raapana (Peter Franzén), a fire-and-brimstone preacher whose Christian sect has dragged many of the already devout locals away from Olle’s church? Or Sulander (Järmo Mäkinen), the seedy printer who publishes Raapana’s religious tracts? Or even the local police, who are demonstratively suspicious of Vares as he pokes into their business?

Not for the first time, the Vares series tests the limits of the Finnish acting profession. The constant need for fresh murder bait, it seems, has exhausted the entire crop of this year’s young Finnish starlets, leaving this episode’s love-interest in the more mature hands of Elisabeth (Merja Larivaara), Raapana’s sexually frustrated wife. Meanwhile, the bent doctor Hento, who secretly prescribes her birth control pills, is played by Kari-Pekka Toivonen, who previously played another role in the second Vares film, Frozen Angel. Famous Finnish crooner Kari Tapio, no stranger to provincial barn dances full of murderous banjo-twanging cultists, I am sure, appears as himself in a concert scene.

Legend has it that the four 2011-12 Vares films were shot back-to-back on a 120-day schedule. And someone has certainly made the most of the economies of scale, presumably shooting a bunch of top-and-tail pub scenes with our hero’s drinking buddies that will suffice for all four movies, while another crew gets on with the aerials. Lauri Törhönen could have been off shooting the prison break sequence for Garter Snake, which involves none of the regulars, while Anders Engström was off with the leading man in the countryside, banking this low-key, low-budget diversion almost entirely featuring a guest cast, released straight to video in 2012.

So even though we begin with the usual overhead shot of summertime Turku, the shadow of the helicopter visible in frame as if to advertise the money spent – no drone footage here! – the bulk of Path of the Righteous Men is set in Ostrobothnia, on the Finnish Baltic coast. Considering the Vares serial’s ongoing feud with things Swedish, I am rather surprised they didn’t make more of the region’s Swedishness. Even its name, “East of the [Gulf of] Bothnia” rather than the more logical “West Finland”, parses it in terms of its geographical relationship to Sweden. I drove through the area once researching the John Grafton incident, and the road signs were in Swedish first and Finnish second. Instead, the script by Mika Karttunen and Katariina Souri, and presumably the 1992 Reijo Mäki novel Vares ja kaidan tien kulkijat on which it is based, focuses on another element of the Finnish hinterland, religious fundamentalism.

It’s certainly refreshing to take Vares out of his Turku home to see a little of the countryside, packed off to a dry county where only low-alcohol beer is available, and his landlord gets a telling-off from the police if he lets him have a snifter of brandy. Raapana’s happy-clappy sect all seems mostly harmless, until Vares realises that the preacher is offering places in heaven in exchange for donations of real estate. There’s certainly something fishy going on, and Vares soon finds himself wading hip-deep into the tawdry secrets of a one-horse town. It’s not clear to me, however, to what extent he actually solves all the mysteries – as with the novels by Reijo Mäki, which mix first- and third-person narratives, there are some scenes of vital exposition that take place when Vares is absent. He certainly stumbles across the truth of who committed the murder, but the degree to which he leaves town having solved all the crimes witnessed by the audience is debatable.

Jonathan Clements is the author of The Armchair Traveller’s History of Finland.

Sukkanauhakäärme (1989) was one of the earliest Vares novels, set at a time when our hero was still fixated on the life he almost had as a big-shot lawyer. Some faint echoes of this remain in Lauri Törhönen’s 2011 film adaptation, in which Jussi Vares takes on a job tracking attorney Pauli Kontio’s unfaithful wife Annika (Rebecca Viitala), at least partly out of envy for the client seemingly having it all.

Someone who is most definitely having it all is Jesus Lobo (Ilkka Villi), a smarmy piano player who seems to have tupped half the women in Turku. Vares starts tailing him with the expectation that he has found Mrs Kontio’s lover, only to discover that Lobo has a girl in every piano bar. He also tinkles the ivories on the ferry to Stockholm, which makes him an ideal mule for drugs and “special” Swedish porn, the nature of which is never revealed, but presumably involves lukewarm saunas and insufferable smugness. As ever in Vares, Sweden is the source of all criminality and torment, a sinful utopia at the other end of the ferry lines.

Meanwhile, Torsten Rapp (Petri Manninen) busts out of jail. If that sounds like a non sequitur, it is for most of the movie, which begins with the prolonged preparations for a jailbreak. But as soon as Rapp has fought his way out of prison with a guard’s uniform dyed blue with toilet bleach, and an improvised shotgun made out of a crutch, he disappears for half the running time, only popping up again at the end for the now-traditional sequence in which one set of criminals is trumped by an even more violent thug, allowing Vares to save himself and the day by dropping between the cracks and cleaning up the mess they leave behind.

Even by the standards of the Vares films, this is a low-rent offering much more on the straight-to-video end. You can even see this in the box-art, which features a sexy, suspendered thigh flashing a snake tattoo on the DVD cover, but hides this behind a more demure basque version on the cardboard sleeve. This is pretty much all there is to say about the titular “Garter Snake” – an epithet directed at a femme fatale in a throwaway line, but otherwise nothing to do with the film at all. Our hero, meanwhile, finally gets behind the wheel of a car, tooling around town in an old Volvo before someone blows it up.

Vares, as usual, spends most of his time blundering between Turku’s watering holes – a Vares drinking game could only avoid alcohol poisoning if viewers took a sip whenever a glass wasn’t in his hand. We can only imagine the product-placement bingo that precedes each shoot, as the cast roll up in some guy’s pub and offer to make sure the sign gets into shot, as long as everyone can have free booze. In one scene, Vares and his friends each have two drinks in front of them, as if they are desperately trying to cram one more in before closing time. The fact that this was the earliest chronological Vares book to be adapted for the screen also creates a continuity confusion, as Vares “finally” sleeps with his perky part-time stripper neighbour Anna (Maria Järvenhelmi), even though she has been acting like his occasional squeeze in the four previous films.

Jonathan Clements is the author of The Armchair Traveller’s History of Finland.