Eight detective stories

Every crime story follows a certain set of rules. Mathematics professor Grant McAllister managed to work them out and hid their secrets in a collection of detective short stories he wrote. Then he disappeared. Thirty years later, Grant is tracked down by an ambitious editor, Julia Hart, who wants to republish his book and travels to a remote island to find him. But there's something strange about his detective stories. Can Julia find the answers to all the burning questions?