The story is about diving into the sun. Likewise it starts slow and easy, everything is just fine and nice. Slowly tension builds up, people and events get nervous until everything reaches unbelieable chaotic state just before the end.
Lots of references to Solaris (the better one), 2001 Space Odyssey, Alien and Event Horizon. Pleasure to watch, even though it's not the easiest one. The audience is required to think during the movie!