Visible crew/equipment: When Dick wants to go along with Mary to a wedding he tries to convince her. When he says "Whatever it takes, I'll do it" he walks forward. Take a look at the top of the screen and you'll notice the shadow of the boom mic on the wall following him.
Other mistake: Sally mentions that she makes jello with cheese, but many times the aliens have shown that they are terrified of Jello.
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Tricky Dick - S3-E3
Trivia: Dick's rant about his perceived evils of rock music is identical to Reverend Moore's (also played by John Lithgow) opposition to dancing from the film "Footloose."
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