Emperor Yuramoto’s crown jewel was recently auctioned, but it turned out to be a counterfeit. Although the cops have a strong suspicion on a criminal mastermind, they are unable to find any evidence against him.

In the hope of finding the real 20-carat diamond and detaining the suspect, they want Mr. Spylock and his team of detectives to conduct a thorough search of the suspect’s den and navigate the puzzling maze laid out by him.