Teenage Mutant Ninja Turtles (1987) Season 4 Episode 7

When Donatello says, "Relax, its wax! We got it out from Flem;s museum!", he's using Leonardo's voice.

In the scene where the turtles are walking through the museum looking for April, Donatello begins to speak and he's using Raphael's voice. Halfway through his line, the screen changes to a view showing all the turtles and Donatello and Raphael have switched places with Raphael continuing the line as if he had been saying it from the beginning!

While Monroe Q. Flem is saying "Oh, my priceless turtles are here! Soon, my collection will be complete!" His mouth doesn't open for the first half of that line being said.

Flem seems to know the interior of the Turtles' lair

When the background shot of the wax statues are shown on Flem's video monitor, they are coloured in all grey