Way, way, way too long. Barely any story in the 860 pages, it gets some drama around 85% in and holds on for a short while.
It's a shame because the first pages are gripping. Then it's just gripping you for an absolute age and it's just a drag.
Nice idea, stretched beyond a reasonable point. Could have easily been an impressive 300 page book.
But it's not. It's a slog.
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