4.25*-4.5* - really enjoyed this and for a debut is truly an astounding novel. Loved the humour, tension, and world that is built through Mark's narrative. Read Project Hail Mary before this and I think overall I preferred the story and characters in that novel which is why this didn't hit 4.5 or 5* as I didn't quite connect with Mark as much. Overall though, really enjoyed it and thought the audiobook experience really did make it even better.