CHECK OUT THE NEW PROLOGUE FILM FOR ALIEN: COVENANT WHICH EXPLAINS WHAT HAPPENS RIGHT AFTER PROMETHEUS!

Alien: Covenant made an effort to delineate itself as a prequel to Alien, though it's still really kind of a Prometheus 2. 

Though director Ridley Scott has switched perspective from Noomi Rapace's Dr. Elizabeth Shaw to a brand new reel of faces, the crew of the colony ship The Covenant, the narrative still leads them to the planet eventually occupied solely by creepy android David (Michael Fassbender).

Which leaves a pretty large chunk of the story untold, now succinctly filled in with prologue film The Crossing, which tracks the journey Shaw and David set off on at the end of Prometheus, bound straight for the homeworld of the Engineers.

First off, it offers an explanation as to why David won't still be the detached humanoid head rolling around we see at the end of Prometheus, with Shaw carefully reconstructing him in an act of kindness that he'd never before experienced, certainly not from the Weyland Corporation that manufactured him. 

We then see Shaw at the controls of the Engineers' ship, with David putting her into suspended animation after she sets a course for their destination, leaving the android entirely alone. However, when the ship finally arrives, Shaw is nowhere to be seen; David looks down at a vast city built by the Engineers, with something of a sinister glint in his eye. 

With a previous trailer hinting that Shaw died on the ship, it's a wonder what exactly happened to David during his time alone, and what kind of revelations he may have come to.