In the "Sanctuary" arc of the original Saint Seiya TV series the production company got a lot of mileage out of a single DID idea:
In episode #60, around 10:00, the ancient Greek myth of Andromeda was explained, and as a visual aid we got an image of a babe, arms outstretched, thoroughly wrapped in chains. (This was briefly repeated in the recap at the beginning of the following episode.)
In episode #68, around 13:00, the myth came up again, but instead of reusing the previous drawing there was a new image of the same babe in the same pose. (I'll bet somebody on the staff was really eager to do that!)
In episode #69, around 13:15, the first drawing was used as a transparent overlay.
Finally, in episode #70, around 22:30, the first drawing was shown again, but in mirror image. (This was briefly repeated in the recap of the following episode.)
Anime Sightings Old and New - Saint Seiya "Sanctuary" Arc
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