This past Wednesday was #AlienDay, a day 20th Century Fox designated to celebrate the legacy of the franchise that started with 1979’s Ridley Scott-directed horror classic and which continues with the upcoming release of Alien: Covenant. It’s a publicity stunt, to be sure, and involved live events on the Fox lot with the cast of the upcoming movie and lots more. Unlike many current similar movies, Alien was not intended as the first in a series of movies. Indeed it was seven years before James Cameron directed the more action-oriented sequel.

The original Alien is, unlike most of its sequels, more concerned with tension and terror than with dramatic fights featuring huge robotic exoskeletons and the creepy crawly alpha predators that lurk in the far reaches of space. Sigourney Weaver stars as Ripley, one member of the crew of the Nostromo, a merchant ship that picks up a distress call emanating from a nearby moon. When they land to investigate they find the ship has been infiltrated by an alien lifeform that isn’t content to destroy but needs the people aboard the Nostromo to propagate and, hopefully, spread to other planets.

The theatrical poster has become so iconic it’s easy to overlook just how much is going on with its design. The title treatment is the lowest-key part of the poster, appearing in simple block letters at the top. The main element is in the middle, the rocky egg that is starting to split, a strange green light emanating from inside and a foggy smoke pouring out. “In space no one can hear you scream” we’re told in the copy that’s just below that. Finally, at the bottom, we see another soft green light just breaking over the horizon of a strange, hatched groundwork that’s clearly meant to look foreign or otherworldly.

It’s a great example of showing just enough to titillate or entice the audience without needing to show off the actual alien that will be hunting the human crew members. In fact not only is there little to nothing shown, there’s very little about the story here, but in a good way. It’s all about the suggestion of danger, of something that’s about to emerge. That’s very different – and much more effective – than those that just don’t show anything about the movie but also don’t leave any room for the audience to imagine what’s happening or what’s next.

The trailer starts off with a full 50 seconds of tracking shots that alternate between covering an alien terrain of some kind and showing the egg, all as the title is slowly unveiled. That helps to establish a sense of mystery as the audience is left wondering where we are and what’s going on with that egg, which eventually starts cracking as the same green light we saw on the trailer comes out. After it cracks we shift to footage from the movie, though there’s no clear story outlined other than “survival.” We see the cast of the Nostromo running through the ship, convulsing for unknown reasons and just trying to not die.

There are no names given here, no characters explained or backstories offered. There’s no synopsis of the story or other insights into what’s happening for the audience to latch on to. That all means it’s being sold as a horror film, not necessarily a science-fiction story. The H.R. Giger-inspired designs are shown prominently throughout the second half of the trailer, again giving people a clear sense that this is a dark, foreign place we’re visiting.

All in all The campaign was much more about selling a mystery and a horror film than anything else. While the series eventually veered into straightforward sci-fi (with the exception of Alien 3, the David Fincher-directed installment that reintroduced a sense of tension), taking the approach of hinting at and alluding to instead of showing outright. What’s unseen is often more terrifying than what’s shown, and the marketing for this 1979 classic embraces that wholeheartedly.