Part near-future thriller set in yakusa Japan and Sarf London, part SF set in far-far-far-future Earth, this is a hard book to summarize. The thriller part dominates, and seems to be set 15 years in the future mostly so our hero can have some bad memories from Iraq in his youth. The SF element nearly makes sense, but it’s not an SF novel for beginners.
I’ve read one other novel by Grimwood, Pashazade. This is similar, but at the same time almost completely different. Recommended.