Kidnapped and taken to China, Sherlock finds himself plunged into adventure. How can three men be bitten by the same poisonous snake in different parts of Shanghai? Who wants them dead, and why? The answer seems to lie in a message hidden in a diagram that looks like a spider's web. But solving it leads to an even more urgent question: what has all this got to do with a plot to blow up an American warship? Sherlock is about to brave terrors greater than any he has faced before Sherlock Holmes. Think you know him? Think again.