
Continuity mistake: When Richie gets up from a table at Arnold's to meet with the Fonz in the men's room he's wearing jeans. When he enters the men's room he's wearing grey slacks. (00:07:50)

Visible crew/equipment: When Al, Fonzie, and Howard use "Gulper" in the diner's kitchen, it starts to throw salad all over. You can see the same hand twice in a short period throwing salad from the door window. (00:13:40)
Answer: If all the actors and hands know their roles well enough they could perform the play reasonably well even without a director.
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