This is a trailer for Red Sand, an ambitious fan film billing itself as a prequel to the events of the Mass Effect trilogy of video games. What makes me bring this to your attention is the fact it stars a guy called Mark Meer.
Who is the voice actor behind the male Commander Shepard in the games.
Confusingly, he's not actually playing Shepard (which is lucky, because he looks nothing like the Dutch model who the character is actually based on), but the role of Colonel Jon Grissom, an Alliance soldier tasked with defending Prothean relics found on Mars.
The not-playing-Shepard thing also makes sense when you consider Red Sand is set 35 years before the first game.