Continuity mistake: When Max pulls all of the money out of the telephone, in one angle the telephone is pouring out coins, but in another nothing is happening.
The Wax Max - S3-E20
Other mistake: When there's a close up of Max firing the rifle, the rides that appear in the next shot should have been visible right behind him.
The Wax Max - S3-E20
Revealing mistake: In the tunnel of Love scene, one shot shows an axe being thrust down at Max. The axe is visibly blunt.
The Wax Max - S3-E20
Visible crew/equipment: When an arrow is fired at the boat in the Tunnel of Love scene, the wire attached to it is visible.
Viva Smart - S3-E2
Factual error: When the soldiers fire their rifles at the start of the episode, there should be smoke or muzzle flash at the end of the barrel, but nothing happens.
Viva Smart - S3-E2
Revealing mistake: The drawers in Max's hotel room have no bottom part in them, but Max passes right between the two drawers when he straightens up, so they have no inside-facing part either.
Viva Smart - S3-E2
Other mistake: The glass of lemonade that the room service drinks is poisoned. The room service says it's for the other room when Max tries to drink it, but if you look closely, Don Adams does drink a bit of the liquid, so he should have died.
Viva Smart - S3-E2
Continuity mistake: At the carnival scene, the shot zooming in on the square shows that the Juggler's balls are blue. In all the other shots, they are white.
Viva Smart - S3-E2
Revealing mistake: The juggler accidentally drops the ball in his act, but if you look at the final part of his performance, he deliberately holds one of the balls in his hands so he can miss the final one.
Viva Smart - S3-E2
Other mistake: At the carnival scene, in one a close-up shots of Max and 99 performing, a female extra in one of the windows waves at the camera.
The Spy Who Met Himself - S3-E1
Revealing mistake: When the fake Chief calls Max over to the car, the driver is meant to be a double of Smart, but the driver is not Don Adams.
The Spy Who Met Himself - S3-E1
Other mistake: During the fight scene at the airport, Smart grabs a handful of soil from a nearby potted plant... Which has no plant in it and is just a random pot of soil in the middle of an airport.
The Spy Who Met Himself - S3-E1
Audio problem: When Max hits the real 13, he misses the punch completely.
Other mistake: The same dungeon set is used several times throughout the series, just furnished differently.
The Spy Who Met Himself - S3-E1
Revealing mistake: When Max is thrown in the dungeon, the man being dragged down the steps is not Don Adams.
The Spy Who Met Himself - S3-E1
Revealing mistake: In a few shots of the dungeon scene, both Maxes are shown. The one with his back to the camera has a different-shaped head to Don Adams, revealing him as a double.
The Spy Who Met Himself - S3-E1
Other mistake: Max cuts through bars to escape his prison cell, but when he cuts them, he does the top part of two of them, and then the bottom part of only the left one.
The Spy Who Met Himself - S3-E1
Revealing mistake: Siegfried shoots his two thugs, but neither one has a bullet hole in their jackets when they get shot.
The Mess of Adrian Listenger - S5-E18
Continuity mistake: Max and 99 are sitting on the sofa. There is a knock at the door and Max fires 3 bullets into the door from a gun. Later, the same day the door is shown behind Max and 99 and there no gunshot holes in the door. Also, 99 changed her clothes and Max still has on the same clothes. (00:09:00 - 00:19:00)
Witness for the Persecution - S3-E3
Plot hole: In this episode, the villain makes a phone call to KAOS headquarters when he's captured demanding that they kill Max to stop him testifying in court against him. Later, several say that Max is the only witness to the villain's crimes, but the Chief and 99 were in the room when the villain made the call, so they could have been witnesses to "conspiracy to commit murder."