You can keep your Scandi noir. What about northern French forensic-thriller farce? This is the latest film from that quite extraordinary French director, Bruno Dumont. He has decided to vacate his creative heartland of fierce social realism in favour of acid black comedy – an epic designed originally to be shown on TV in four 50-minute parts – starring Bernard Pruvost and Philippe Jore as Van Der Weyden and Carpentier, two incompetent rural cops on the trail of a serial killer who leaves body parts inside barnyard animals.

Their bumblings are dispassionately observed by a local kid, P’tit Quinquin, or Lil’ Quinquin (newcomer Alane Delhaye): it’s a group-guilt phenomenon that discloses sexual intrigue and xenophobia. Dumont’s apparent shift from tragedy to comedy may not be as inexplicable as all that: he has touched a few of the dials on his creative dashboard and given a different hue and style to the same vision. He always did subvert the social realism with surrealism.

At any rate, P’tit Quinquin revisits the themes and tropes of Dumont’s early film L’Humanité (1999): grisly murders in a small northern French town, with an imbecile cop tracking down the culprit. Van Der Weyden is the deeply odd investigating officer; he and his partner are horrified by the killer’s MO and compare it to Zola’s La Bête Humaine. Later, a severed head is found that looks a little like Laura in Twin Peaks; Dumont has the same Lynchian interest in using a bizarre criminal event to make audible the hitherto silent hum of weirdness in a small parochial community.

Dumont’s supernaturally insoluble crimes are also influenced by Antonioni and Haneke, and his outrageous comic turns have also taken something from the French deadpan comedy specialists Benoît Delépine and Gustave Kervern. It really is very strange, and the funeral scene in the first act must be the weirdest and funniest moment of the year.