Revealing mistake: When Hymie does the high jump, when the film cuts to a shot of him clearing the bar, Hymie's hair is curly when it should be flattened down like when he took of and as he landed. It is obviously a stunt double.
Plot hole: The scheme to lead a blindfolded Max and 99 to what they think is the airport via an illusion room would not work the way they do it. Since the base is underground, there is no way that what they did to represent ascending to ground level that would make a person think they were above ground.
Visible crew/equipment: In the motorcycle joust sequence, when the Purple Knight falls off his bicycle, his helmet flips up and you can see it's a stunt double - the Purple Knight's beard is gone.
That Old Gang of Mine - S3-E10
Visible crew/equipment: When the Turk is breaking into the palace, he pushes the window and it just swings open, since it is unlocked. However, you can see hands belonging to a crew member pulling the windows open to make way for the gag.
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."
The Little Black Book: Part 1 - S3-E16
Audio problem: When Max is fighting the waiter, several times he misses the waiter completely, but you can still hear the sound.
Revealing mistake: At the start, when Max falls off his police motor cycle, he is obviously a stunt double.
Visible crew/equipment: Lights are reflected in the aide's glasses when Max and 99 are talking to him on the ground.
Revealing mistake: When the Prime Minister's aide falls out of the car, he is a dummy.
Audio problem: During the joust scene, Max turns around to have another charge at the Knight and the crowd is clapping, but there's no sound at all.
Continuity mistake: During the joust scene, several tyre marks on the ground from the motorcycles disappear from the ground.
Other mistake: The same shot of Max charging on his motorcycle is used twice in less than a minute.
Revealing mistake: During the fight scene in the gymnasium, Max is a blatant stunt double in some shots.
Audio problem: When Max is freed from the chains and punches the biker, he misses the punch completely, but the guy falls over.
Revealing mistake: When Max writes down the code and hands it to Hercules, the paper is blank the entire time.
Other mistake: Max collapses and spills the antidote on the floor, but there are no wet marks when the Chief bursts into the room.
Audio problem: When in the apartment of the doctor, it is raining, but there's no sound from the rain hitting the building.
Suggested correction: I've been in several different buildings where I can't hear the rain. Even in my own home there's times I can't hear the rain, even though other times I can.
Continuity mistake: When confronted by Siegfried in the restaurant, the position of Siegfried's gun compared to Max's head changes constantly between shots with no time to move.
Visible crew/equipment: When Siegfried throws the cup into the air and Doctor T holds it up with his force field, a wire is visible holding the cup in the air.
When Good Fellows Get Together - S3-E8
Revealing mistake: In the final scene when Hymie is fighting Groppo, Hymie is a blatant stunt double in several shots, evidenced by the different shaped head of the double.