The idyllic small town of Bailey Downs receives something far worse than coal in its stocking in "A Christmas Horror Story," a "Trick 'r Treat"-esque anthology of interwoven horror tales set on Christmas Eve. Deviously shrewd in its conception while belying its presumably modest budget—production values, complete with lonesome, snow-blanketed locales and a hefty narrative scope, are impressive—the film isn't consistently successful across all four storylines, but cooks up a purveying sense of fun and dread all the same.

The two strongest threads are directed with tautly wicked glee by Grant Harvey (2004's "Ginger Snaps Back: The Beginning"). In one, a troubled family—police investigator Scott (Adrian Holmes), his wife Kim (Oluniké Adeliy), and their young asthmatic son Will (Orion John)—trespass on private property in search of the perfect Christmas tree. The parents experience a scare when Will briefly goes missing in the forest, but a more frightening experience awaits them once they return home with someone who may not be their son at all. In the other home-run story, a bickering family's (Jeff Clarke, Michelle Nolden, Amy Forsyth, Percy Hynes-White) visit to butter up their wealthy Aunt Edda (Corinne Conley) takes a ghastly turn when their naughty ways unleash the murderous wrath of anti-Santa demon Krampus (Rob Archer). Krampus, a horned, hulking, chalky-skinned figure of part-human, part-otherworldly alpine descent, is spectacularly designed and performed by Rob Archer, used sparingly enough to retain a continuous menace.

The weakest link of the four connected episodes finds three high school friends—Molly (Zoé de Grand'Maison), Ben (Alex Ozerov) and Dylan (Shannon Kook)—sneaking into a private academy to shoot a school assignment about an unsolved double murder that occurred there a year earlier. Once locked inside the basement, it soon becomes clear a supernatural entity is lurking with them on the grounds. This particular story, directed by Brett Sullivan (2004's "Ginger Snaps 2: Unleashed"), wastes the potential of a genuinely chilling backdrop of unused nativity scene mannequins for a shaggier, less interesting premise involving ghosts and possession. The fourth, helmed by Steven Hoban, takes the viewer to the North Pole, where Santa (George Buza) and Mrs. Claus (Debra McCabe) are terrorized by their once-cute, suddenly zombified elves.

"A Christmas Horror Story" lands the setups more than the payoffs of the respective tales, but adds an ingenious jolt to the finale impossible to see coming. Meanwhile, hovering over the proceedings is Bailey Downs radio deejay Dangerous Dan (William Shatner), playing Christmas chestnuts in between reports of a hostage situation taking place at the local mall. From the creepy-cool opening credits scored to a child's cover rendition of "Carol of the Bells," to the clever juggling of subgenres, to the rich atmospheric pall hanging like blood-spattered candy canes across the mantle, there is a lot to like in spite of the picture's uneven script. Audiences who prefer their holidays with a dose of darkness and foreboding to offset the season's syrupy mirth should really take to "A Christmas Horror Story."