“The question mark,” Jupiter said impressively, “is the universal symbol of something unknown. We are prepared to solve any puzzle, riddle, mystery, enigma or conundrum which may be brought to us. Hence the question mark will be our trade-mark. Three question marks will stand for The Three Investigators.”

“The question mark,” Jupiter said impressively, “is the universal symbol of something unknown. We are prepared to solve any puzzle, riddle, mystery, enigma or conundrum which may be brought to us. Hence the question mark will be our trade-mark. Three question marks will stand for The Three Investigators.”

— Robert Arthur