Who is he, really? He doesn't know, doesn't remember anything. Absolutely nothing. The only thing he knows is that he just woke up from a strange, deep sleep that seems to have lasted years, that the only other presence in his environment is a computer voice and four terrifying robotic arms, which, however, take care of him, and that in the adjacent bunks there are two mummified corpses.

Days will pass before he remembers: He is a high school science teacher. His name is Ryland Grace. He is the sole survivor of a mission to save humanity. He is on a spaceship, in a distant solar system, exploring it alongside his buried memories – a dual "journey" that confronts him with increasingly astonishing surprises.

This is how this thrilling story begins from the author of the book The Martian. The sequel is even more exhilarating. Ryland has a significant mission to accomplish, no matter how alone he feels so far from Earth. But is he really alone? Safe travels.