This is a generally entertaining book that would particularly suit A-level science students, or adults with a general interest in science but no deep knowledge. It covers nine scientific "paradoxes", some very well known and others more specialist. The style of writing is informal, sometimes excessively so, but clear and engaging. Some of the discussions of the paradoxes felt like they could have done with more explanation, rather being left having to take Al-khalili's word for it, but I suppose a balance had to be struck between detail and readability. One example of this is Olber's Paradox - why the sky is dark at night. Al-khalili suggests that darkness of the night sky is proof of the Big Bang, but doesn't really provide enough detail to show anything more than that the dark sky is *consistent* with the occurrence of the Big Bang. Notwithstanding that, the book's a good read.