GET DOWN AND GET FUNKY. AGAIN. CONTAINS SPOILERS.
It's always the way. You wait years, maybe even decades, for a low-budget grindhouse-inspired disco/splatter horror comedy mashup and then two come along at once. The Disco Exorcist was unutterably worthless; this is at least forty-three thousand times better thanks to impeccable production design, some decent acting, and more than a mere sense of basic professional competence on both sides of the camera rather than a bunch of halfwits throwing it together for a laugh. That's not to say Renaud Gauthier's Discopath is a classic: it veers too wildly in tone from daft comedy to bloody gore, but it gets closer to the grindhouse tone than many.
Duane Lewis is the Discopath: an ordinary young New Yorker who turns into a mad killer every time he hears disco music due to a traumatic incident in his childhood. Driven to kill his date at a local club (memorably leaving her dying under the transparent dance floor, unnoticed by the dancers), he flees to Canada under an assumed identity, taking a lowly handyman job at a convent school. But it's not long before he hears the music again....and both the local and New York cops on his trail....
To be honest it doesn't really matter too much about the silly plot: it's more about recreating the mood and feel of tatty 70s splatter movies and that's done superbly well with the hair, costumes, sets and period cars as well as some decent gore effects. The production design is fantastic and the film has enough of a grainy look without resorting to the fake print damage gimmick. But it is all over the place: there are funny bits and silly bits and gory bits, so it's rather got the ramshackle feel of one of Troma's wretched gore/comedy combos, though without the childish bad taste and considerably better done.