If Chariot of the Gods is Alien, this movie is Aliens. It's an awesome cinematic scenario with a great story and tons of great alien action. It begins with some good investigation and rp type stuff, but quickly escalates in intensity as the marines deal with trying escape a moon that is quickly becoming overrun with xenomorphs and an invasion by the UPP. One of the things that I like about this scenario is that there are tons of fun event ideas to spice it up, but a lot of them are optional, so the GM has a lot of freedom to control the pacing. It's a pretty long adventure split into 3 acts. At best, you could probably complete one act in a session, but with all the optional event content, you could easily extend it to 2+ sessions per act. The scenario has a number of great maps and the adventure location is very well detailed. As a nice bonus it's available for a couple of the big VTTs.
One caveat- I wouldn't recommend this for a newbie GM. It has a lot of moving parts, and I think you need to be an at least somewhat experienced GM to pull it off well.