When I was very young, like in between 5-10 years old, I'm sure I would have liked this production. Films like "Special Mission Lady Chaplin" (1966) or "Kiss Kiss, Kill Kill" (1966) (Kommissar X series), "The Viscount" (1967), were my favorites. Today, I only think of them as bad jokes. Just like this "Mister X" (1967). Some kind of charm, infantile and childish, it has. Someone compared it to "Danger: Diabolik" (1968), made a year later. Yeah, they have something in common, the character Mister X is like Diabolik's greenhorn-duffer brother. "Danger: Diabolik" is an excellent movie, "Mister X" is just a dumb movie. It can be compared to "The Incredible Paris Incident"(1967), both are at the same level of value, meaning almost zero. If you resist to the end it means you have already fallen asleep or you are dizzy. A lot of talk in the movie will help you out.