The Invisible Professor is a 1959 Felix the Cat cartoon, and the 30th episode of the Felix the Cat (Joe Oriolo) series.
The episode starts with Felix sitting in an office, working as a Private Detective. He's bored out of his skull waiting for something to happen, but gets a phone call about Professor and Rock Bottom. He uses his crime computer, and prints out info on the two crooks. He finds out they're in Schnitzelvania, and heads off to investigate what they're up to. Meanwhile, in his lab, Professor succeeds in finishing his latest creation—invisible paint, which he tests out on Rock Bottom and then on himself. They both head off to the royal palace of Schnitzelvania, with Rock carrying the paint cans (which are also painted invisible) and Professor carrying the brush. In Schnitzelvania, Felix is sitting on a statue, using a telescope to keep an eye out for his foes, but doesn't see any sign of them. At the royal palace, the King reacts in horror as his belongings, like his stamp collection and golden bricks in his safe, are vanishing into thin air, and his guards are no help to this situation. Desperate, he orders the royal strongarms to bring Felix to him. As the king explains the situation, Felix sits down on the open safe, but notices his rump has turned invisible—he immediately deduces that it's invisible paint, so he grabs a magnifying glass and sets off to investigate the source of it. Elsewhere, Professor and Rock Bottom sneak into another part of the castle and use paint remover on themselves. Just as Professor is gloating over all the treasure he's stolen, Felix shows up at the door to try and stop Professor. Rock sneaks up behind Felix and traps him in a rubber glove as Professor laughs at his little victory.
In the second part, Felix is still trapped in the rubber glove, but invokes his title of International Detective and tries to place both Professor and Rock under arrest. Rock just swats Felix out of the way as he and Professor put more invisible paint on to go off and steal more treasure. Felix ponders how to get free, and he sees a vacuum cleaner nearby. He uses it to inflate the glove so much that it explodes. Felix thinks fast about how to stop Professor and Rock, and he notices a paintbrush with invisible paint, paint remover and a bug sprayer nearby. He grabs the tools, paints himself invisible, and heads off. Inside the palace, the King panics as his painting, goldfish and piggy bank vanish into thin air. The King ponders where Felix is, just as the cat shows up in the throne room, invisible and wielding the bug sprayer. He uses it to spray Paint Remover on Rock Bottom, revealing him carrying a wheel-barrel of jewels. Professor gets angry and grabs a sword off the wall. Felix effortlessly dodges as Professor charges forward, with his sword getting jammed into an electrical socket nearby. Felix then sprays him with Paint Remover while he's stunned, and then sprays himself with it and places Professor and Rock under arrest. They both try to run away, but they're quickly grabbed and hoisted into the air by an unseen force. Felix sprays paint remover, revealing that he had given some of the invisible paint to a guard. The King inquires where his gold is, and Felix responds by spraying more remover into the air, revealing more invisible guards had carried his treasure back to the castle safely. The King cheers on Felix, Rock and Professor look on despondently, and Felix laughs as the cartoon irises out.
Tropes:
- Cartoon Bug-Sprayer: Felix uses one to ruin Professor's disguise.
- Freeze-Frame Bonus: Professor's mugshot reveals that his name is Nut-Meg.
- Harmless Electrocution: Professor gets electrocuted by accidentally jamming his sword into a wall socket, but it just stuns him.
- Invisibility Cloak: Professor creates invisible paint.
- Nonchalant Dodge: Felix uses this to trick Professor into jamming his sword into an electrical wall socket.
- Pun: Professor and Rock are hiding out in a country called Schnitzelvania, a play Transylvania. Also, Rock Bottom traps Felix in a rubber glove, and Profesor cracks that it fits him like a glove.
- Shout-Out: When Rock Bottom is being painted a second time, he remarks that it's "Another Rembrandt!"
- Sinister Surveillance: Inverted; Felix's crime computer is able to track down the exact location of Professor and Rock Bottom, but it's used for good purposes.
- Stock Footage: The scene where Professor and Rock paint themselves is used twice in the same episode, complete with the background of Professor's lab and Rock saying they're going back to the palace, even though they're already at the palace.
