Eagle-eyed fans made a surprising discovery in the official Halloween Kills trailer: a clever callback to a lesser-known film in the franchise, Halloween III: Season of the Witch. Considered one of the worst entries in the Halloween series, it's shocking to see this film referenced, but, as is par the course with scary movies, there's always a market for bad horror.

Season of the Witch premiered in 1982 to a lot of backlash and disappointment. The original plan for the Halloween series was to be an anthology of sorts, telling different horror stories and focusing on different characters. However, due to the convoluted storyline of the film and the popularity of Michael Myers, Season of the Witch was a box office disappointment, and the rest of the series refocused on telling the story of the Shape and his victims.

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Halloween III: Season of the Witch's Iconic Masks

A commercial advertises evil masks in Halloween Season Of The Witch

Season of the Witch featured elements of sci-fi and witchcraft rather than the blood and gore slasher focus of the first two Halloween films. While the film had several interesting concepts throughout, they weren’t very fleshed out and just seemed to add to the confusion of the plotline.

The main focus of the film was on Silver Shamrock Novelties -- a company that made and sold popular skull, pumpkin and witch-themed Halloween masks. The masks were marketed along with a “Halloween giveaway” that was promoted throughout the film with a commercial and a catchy jingle that no fan can forget. The twist is that the masks are actually part of a mass sacrificial ritual to resurrect a form of ancient pagan witchcraft and had a bewitched piece of Stonehenge that would be activated by a flashing signal aired during the giveaway, leading to brain rot and unleashing swarms of snakes and insects to attack those nearby. However, from a town massacre to resurrecting ancient witches, the film was full of plot holes and one-off bits of action that didn’t sit well with the initial audience.

It may be considered a cult classic today, but the film received mostly negative reviews upon its debut. Not only was it the worst-performing Halloween movie of the franchise to that point, but it was also outperformed by other horror films released around the same time like Poltergeist and Friday the 13th Part III. With the backlash from Season of the Witch, the anthology idea for subsequent films was scrapped, and the fourth installment once again focused on Michael Myers.

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A Major Callback in Halloween Kills

While it’s unlikely that Halloween Kills will feature any major aspects of Season of the Witch, the trailer still makes reference to the iconic skull, pumpkin and witch masks from Season of the Witch. Despite going through multiple reboots and spin-offs, none of the other films in the franchise have referenced any of the events in Halloween III, making this a monumental occasion for the much-maligned film.

Since its release almost 40 years ago, Season of the Witch has become a cult film among horror fans. It's difficult to pinpoint a specific reason why the consensus has turned, but it might be the collective appreciation of the weird that has allowed Halloween III to finally find a place in horror history. Although a reboot of Season of the Witch may never come to pass, at least a part of the Silver Shamrock company will live on in Halloween Kills.

Directed by David Gordon Green, Halloween Kills stars Jamie Lee Curtis, Judy Greer, Andi Matichak, Anthony Michael Hall, Kyle Richards, Robert Longstreet, Nancy Stephens, Charles Cyphers, James Jude Courtney and Nick Castle. The film arrives in theaters Oct. 15.

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