It is the fourth book in the Amber series.
Another layer of truth is revealed -- and the threat to Amber is more real than anyone realized. Amber's blood has been spilled at its seat of power. Yet explanations for all this have many versions, and which one is real? While Corwin tries to gather enough knowledge to stop his enemies, he understands that his Family is really the cause of what has happened.
But nothing slows in the Chaos invasion of Amber. The Family of Amber may be destroyed before Corwin can find his answers. Even the dark culmination here sings with the personal power conjured by the author.