From Greek mythology’s Lycaon to modern-day Michigan Dogman sightings, werewolves and their regional variants have prowled our imagination since time immemorial. While most cultures had their own particular rules and conventions regarding these creatures (the full-moon shtick is actually a relatively recent addition to the lore), the monster that we now know as the werewolf has the rare honor of being popularized by film instead of literature. And if there’s one werewolf story that stands out as the definitive version of the legend, it’s John Landis‘ 1981 classic An American Werewolf in London.

Featuring both laugh-out-loud jokes and spine-chilling scares, with one element never overshadowing the other, Landis somehow managed to craft a flawless horror-comedy that has yet to be topped. With the film celebrating its 40th anniversary this month, I’d like to take this opportunity to discuss how its perfectly balanced comedic elements are precisely what make it such a unique experience.

Presented like the illegitimate lovechild of a classic folk tale and an 80s sex comedy, An American Werewolf in London tells the story of David Kessler (David Naughton), a young Jewish man from New York backpacking through England with his best friend Jack Goodman (Griffin Dunne). Unfortunately, the duo is attacked by a mysterious creature after stepping foot in the dreaded Yorkshire moors, with Jack being killed and David becoming destined to transform into a savage monster himself. Sympathizing with this lonely stranger in a strange land, Nurse Alex Price (Jenny Agutter) invites him to stay with her in London as police sort things out, leading to a doomed romance as the full moon inevitably approaches.

“Two Americans walk into a British bar. A horror movie ensues.”

There’s obviously a lot more to the story than that, with the added complexity that David might just be suffering from clinical lycanthropy after a traumatic experience (plus a strange but compelling theory that the movie is secretly about processing Jewish trauma, as suggested by Jon Spira’s video essay I Think He’s a Jew: The Werewolf’s Secret), but it’s still not a terribly unusual setup for a monster movie. What really keeps audiences on their toes here is the offbeat way that Landis chooses to depict these events, opting for the comedic route when telling an obviously tragic tale.

A lot of folks don’t even remember the film as a horror-comedy, focusing on the sad and gruesome story of a young man who becomes a monster through no fault of his own. However, on subsequent rewatches, you’ll probably be surprised with how often the movie tries to make you laugh, and even more surprised at how often it succeeds. From that opening “remember the Alamo” joke in the Slaughtered Lamb to the inherent absurdity of David’s undead victims cheerfully trying to convince him to commit suicide, I’d argue that the humor here isn’t meant to simply pad out the runtime in-between nightmarish werewolf sequences, but instead serves a narrative purpose as it makes you grow closer to the protagonist.

With a near-perfect ratio of 50% humor and 50% scares, watching the film feels a lot like hanging out with a playful friend that reacts amusingly even when surrounded by horrible circumstances. This makes it all the more shocking when your buddy turns out to be a terrifying man-eater who’s probably not going to make it out of this situation alive. That’s why I’d say that Landis’ greatest achievement here is in making the movie humorous but never satirical or farcical. The tragic horror elements are treated with the utmost seriousness, and the movie only ever laughs with David, never at him.

This is what makes An American Werewolf in London stand out among other horror films that attempt to be funny. If you think about it, even the most humorous Slasher flick is still depicting the brutal murder of (usually) innocent young men and women, but most horror fans consider these sequences fun instead of scary. That’s because those movies aren’t trying to use humor to generate empathy but to make the overall ride more entertaining. This isn’t necessarily a problem, as not every scary movie needs to make you feel bad about the deaths or the one responsible for them, but it exemplifies how unique Landis’ approach was.

This werewolf doesn’t just look scary, it looks mean.

In fact, with so many accolades describing it as one of the greatest movies ever made, it’s easy to take this film’s bizarre decisions for granted. But make no mistake: this was a weird flick even back in the 80s. With an oddly sudden (but still convincing) romance, niche references to English culture and the odd inclusion of Nazi werewolves in outlandish nightmare sequences that have little-to-no bearing on the plot, this movie clearly shouldn’t work, but does. The heart-wrenching final moments are proof of that.

Cutting abruptly from that shocking finale to the closing credits while blasting one of the most upbeat renditions of Blue Moon ever recorded, some of the film’s more nihilistic fans assume that this ending is meant to be a mean-spirited middle-finger to the audience, as if it suggests that the universe doesn’t care about David’s tragic plight. I have a different opinion, as the rest of the film made a point of showing David trying to make the best of a bad situation. The way I see it, this ending is actually Landis’ way of telling us that, sometimes, the only appropriate reaction is to laugh in the face of tragedy, and I can sympathize with that.

Even after 40 years, there’s still so much to be said about this lovably strange film and how it perpetuated the now-definitive version of the werewolf mythos through humor and genuine pathos. While it’s said that the project’s original financiers were initially hesitant about the script, supposedly claiming that it was “too funny for horror and too scary for comedy”, I’m of the opinion that An American Werewolf in London is exactly funny and scary enough to be one of the greatest achievements of genre filmmaking, as well as one of my all-time favorite movies. So, whether you’re a fan of sincere laughs or just want to watch Rick Baker‘s legendary creature design in action, this is one monster movie that will forever be worth revisiting.

Maybe there’s a little werewolf in all of us.