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.