The world ended two years ago. Surviving on a few lightly populated colony planets, humanity is trying to out-run the creatures that destroyed Earth. The setup and initial plot unfold at breakneck speed. That's something I've noticed more in British SF (as this is) compared to U.S. fiction. You can watch this at work in many Dr. Who episodes -- a lot happens with no time to catch your breath. Anyhow things settle down and it's definitely worth your time if you enjoy vaguely plausible space opera with elements of horror.