Deliberate mistake: The layout of the Walsh house, both interior and exterior, is different in the pilot than it is in the rest of the series.
Other mistake: When the show aired in 1990, in the pilot episode Brenda falls for Jason. She later on reveals herself to be a "16 year old junior" in high school. Season 2 opens up with the gang on summer break which technically would make them going into their senior year. It wasn't until Season 3 that they were going into their senior year. They graduated in 1993 from West Beverly but the show debuted in 1990 so technically they should have been sophomores.
Brandon Walsh: It was good to see you back at the Peach Pit tonight. I know it took a lot of courage.
Brenda Walsh: Brandon, please, I've had quite enough praise for a while.
Brandon Walsh: All right, you're a huge loser. How's that?
Brenda Walsh: Oh, much better.
Trivia: When Brandon and Kelly leave the movie theater, they pass a billboard for The House of Yes, which co-starred Tori Spelling.
Question: In the first few episodes, the Walshes live in a different house than the one they live in throughout the series. Nothing was ever even mentioned, I don't think. Was it a mistake, or did I miss the explanation?
Answer: There was no explanation. Usually, when a show doesn't know if it's going to be picked up or not, they will use stock footage until they can spend the money on a real location.
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