What is the Movie Prometheus About?

I've read that Ridley Scott has directed a new movie called Prometheus and I wanted to know what it's about. It'll be starred by Noomi Rapace and Michael Fassbender, who was in X-men First class, so I think the movie Prometheus is going to be great, but what is it about?
I think it has to do something with aliens but I don't know much about the plot, as the IMDB doesn't say too much about it. What is the movie Prometheus about, can you please let me know the plot?

So far there isn't much information available about the movie Prometheus, because it's new and the producers have decided to keep most of its details a secret.
But as always some information has been leaked, I can tell you that the movie Prometheus is about a group of explorers who discover a clue to the origins of mankind, which leads them on a journey to the darkest places of the universe. On this journey, they will fight a terrifying battle to save the future of the humankind. I think the plot is not very unpredictable but the cast looks great although it's just speculation since we don't know much about what the movie Prometheus is about.