Robert Carlyle and Emma Thompson in Barney Thomson (Gravitas Ventures)

In Barney Thomson, Glasgow is depicted as one of the dreariest places on earth, and poor Barney Thomson is one the dreariest people in it. A barber in the same tiny shop for 20 years, he has grown increasingly surly toward the customers and has been demoted to the farthest barber chair from the main entrance. He’s not so much a despicable person as a desperately pathetic one. He throws childish tantrums, which he then follows with wheezing, blubbering apologies.

Even his mother, a coarse, vulgar harpy of a woman, barely notices him. Apparently his purpose in her life is to drive her to the local bingo hall. He should come across as sad and unlikable and a totally inappropriate protagonist to carry a film, considering the fact that we are expected to sympathize with him. And particularly because he kills a couple of folk. Ah, but Barney Thomson is played by the great Scottish chameleon Robert Carlyle. And Barney Thomson (the film) turns out to a be a dryly hilarious study of someone who tries to pull himself out of a rut and ends up getting himself deeper in the hole.

You see, as Barney commits his murders, truly accidental, there is a serial killer in town mailing body parts to random people (an arm here, an arse there), completely stymieing the local police force, which consists of Holdall (an exquisitely pissed off, self-loathing Ray Winstone), a world weary, former London detective; his eager beaver, puppy-eyed assistant MacPherson (Kevin Guthrie); and their department rival, the driven, obnoxious Detective Inspector June Robinson (the brilliant Scottish comedian Ashley Jensen), who delights in undercutting Holdall and taking credit for herself.

The movie consists of a cat and mouse of sorts in which Holdall suspects Barney of all the serial murders, and Barney, who is so inept at being a murder AND pretending not to be a murderer, practically falls into Holdall’s lap, yet no one can believe a slubbering blob of humanity like Barney could be capable of anything. And then there’s Barney’s mom, Cemolina, who Barney turns to for help and who seems a little too capable of disposing dead bodies.

The best way to describe Barney Thomson is a black comedy or, more to the point, a bleak comedy. This is human nature writ dark, with tiny, miserable little complaints and petty jealousies that just burn through the characters. In the beginning, Barney loses his job at a barber shop where he is utterly miserable, but his pride keeps him from leaving after he is fired. Holdall wants to solve the case so that Robinson can’t get at it and vice versa, yet they could give two craps about the victims.

And then there’s Cemolina, an epically self-centered harridan. She’s loud, vulgar, frequently drunk, and the bane and salvation of her poor son’s existence. Barney has a total awareness of her awfulness but a loving son’s devotion to her anyway. Cemolina is played with crack timing and a complete lack of social inhibition by Emma Thompson. Five years older than Carlyle in actuality, Thompson ditches prosthetics for the most part and employs the great old-fashioned art of acting, altering her posture and piling on the most garish of clothing to embody one of the most excruciatingly unpleasant comic characters in decades.

Robert Carlyle also directed Barney Thomson, and he definitely shows a keen sympathy for the downtrodden and the unnoticed. He also has a sense that the comedy needs to build, as it’s based on character, so he allows the story to breathe before hitting you with a precisely executed laugh-out-load set piece. (Barney’s attempt to hide a body in his co-worker’s apartment in an attempt to frame him is a fine example.)

For sure, Barney Thomson is off-kilter and not remotely standard comedic fare, but sit with it for a bit and you’ll find yourself engrossed in a twisted little gem of a comedy.