Mr. Dingle, the Strong - S2-E19
Question: What was the reason for giving Mr. Dingle super strength?
The Eye of the Beholder - S2-E6
Question: Why were two different actress used for the character of Janet Tyler?
Answer: Apparently, the producers wanted a specific look for the face that would be unveiled by the removal of the surgical bandages. Actress Donna Douglas was that face chosen to portray the "ugly" woman, outcast from a State Dictatorship of pig-faced humanoids which values conformity over all else. The voice of actress Maxine Stuart was chosen to portray the desperation and urgency of a patient whose only goal is to fit the "norm." It may seem unusual that they couldn't find one actress with both the looks and the voice required by the role. In this case, it added a certain level of surprise at the reveal, as the face we see isn't the one most of us imagined by the voice alone. But it isn't the only time in Hollywood history when voice and actor haven't matched. Singing voices in musicals were often dubbed over by an alternative performer, rather than finding one actor/actress who could both act and sing the role. And dubbing of a different voice actor has also been used for dramatic effect in other instances, as well. Chalk it up to a dramatic decision.
Answer: It's explained in the episode. The aliens are experimenting to see how humans react to various scenarios. This just happens to involve them using super strength.
Thanks. It's been a long time since I saw the episode so I forgot.