Below, Heat Vision has assembled a refresher course on what you truly need to know before seeing Alien: Covenant.

Engineers made Alien Xenomorphs to be used as biological weapons.

It has been quite a few years since Prometheus hit the big screen. So here's a refresher: Most of the movie dealt with the crew of the space ship Prometheus trying to communicate with an alien group we call the Engineers. We are led to believe that these engineers brought life to Earth, and as the movie unfolds, we learn they have created biological weapons to take that life away. Fortunately for us, they never made it back to Earth.

Little is known about the parasitic life forms the Engineers created, but most of the creatures are connected to a mysterious black goo. Many different species who want nothing more than to infect another biological life form live in the goo, but the goo itself is also able to cause mutations.

The survivors of the Prometheus went off to find the Engineers at the end of the film.

Let's go back even further, and look at how Prometheus began: After coordinates to a distant planet were discovered in cave paintings around the world, the voyage of Prometheus was commissioned by the elderly and terminally ill Peter Weyland (Guy Pearce), in a attempt to speak to his creators, and as a last-ditch effort to learn the secret to immortality. Weyland failed, and he and entire crew of Prometheus were killed, except for Elizabeth Shaw (Noomi Rapace) and the severely damaged android, David (Michael Fassender) — whom, by the way, Weyland himself created. After learning the Engineer's plan, Shaw and David set off in a space ship for the Engineer's home world in an attempt to understand why they wanted to destroy the human race that they themselves had created.

Different types of Aliens are created after cross-species infections.

Not until the closing moments of Prometheus did we even understand how the events from the film tied into the Alien universe. David, an android with mysterious motivations, inexplicably infects shipmate Charlie (Logan Marshall-Green) with a small drop of the black goo in his drink (it seems David, an artificial creation, has an interest in becoming a creator himself). After Charlie makes love to his wife Elizabeth, he unknowingly passes on an infection of a squid-like alien. In a horrifically memorable scene, Elizabeth is forced to have an automated Cesarean section to remove it (without anesthesia). Later in the film, a squid alien (officially known as a Trilobite) has grown considerably larger than the Engineer it captures, and ends up parasitically infecting the Engineer as well. In the closing moments of the film, we see a new alien burst from the Engineer's chest. The surprise is, this alien, spawned from a single drop of black goo, cross-infected by two human hosts, a squid alien and an Engineer, looks more like the Alien Xenomorphs that we're already familiar with from the Alien franchise.

Alien facehuggers don't exclusively infect humans.

Throughout the entire franchise, we've seen alien facehuggers infect humans, creating the Xenomorph that we are so accustomed to. There are actually more infection possibilities than just humans, as seen in 1992's Alien 3, when we see a face hugger infect a dog. This alien Xenomorph was faster than most, and ran on all fours, taking some traits from its canine host. In the directors cut of Alien 3, we see a Xenomorph spawned from a bull. The only other time we have seen the series experiment with different types of Xenomorphs was with a “Predalien” in Alien vs Predator: Requiem, but it is better if we just forget about that movie all together. But keep all of this in mind when seeing Covenant.

Xenomorphs behave differently if they are in proximity to their queen.

In Alien, we get a lone-wolf Xenomorph stalking the crew of a space ship on its return to Earth. In the sequel, Aliens, we witness more of the "hive mind experience." In this movie, we see Xenomorphs capture the young character Newt (Carrie Henn), in order to take her back to the queen for infection. In films featuring no queen, the Xenomorphs have only one goal: kill everything. Our point: it's important to remember that yes, depending on who they are around, a Xenomorph may act differently.

Alien: Covenant opens Friday. Stay tuned to Heat Vision for much more.