(1965) Fourth in the Three Investigators series of juvenile mysteries, and the first that I found disappointing. One of the villains is modeled on Fu Manchu, of whom I have recently had more than my fill thank you, and the explanation for the mystery is cartoonishly unsatisfying. Still, it's the Three Investigators and I can't dislike them much.
This was my #DoubleSpin for August.
@TheAromaofBooks