Revealing mistake: The doorway inside Quinn's house on ice-world is lined with snow-covered icicles. Watch as Arturo walks through this doorway; he bumps into the icicles and you can see that it is just a bunch of cotton.
Sliders (1995)
1 revealing mistake in season 1 - chronological order
Greatfellas - S2-E10
Deliberate mistake: When Quinn comes back to the hotel room with a large stack of money he'd won at the casino, he waves it, and you can see a 1-dollar bill in the middle. He was supposed to have over $100,000, but since the crew couldn't get that much money for a brief scene, they used a stack of dollar bills. (00:35:40)
Just Say Yes - S4-E7
Agent Lowell: That's Mallory all right. Busted twice for non-possession. Jumped bail a year ago and ran off to Mexico.
Damon: I heard he died of an under-dose.
Agent Lowell: Same here. I guess we were wrong, huh? It's a safe bet Mallory snuck back into the country to spread more of his anti-drug propaganda. A guy like that shouldn't be on the street.
Trivia: The man who is homeless in "our" world, and is running for the U.S. Senator in the parallel universe, is the episode's director, Andy Tennant, making a memorable cameo appearance.
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Suggested correction: The homeless man (Crazy Kenny) was played by Frank C. Turner, not Andy Tennant.
Question: The four main protagonists are constantly sliding into a different universe, with just the clothes on their backs, and they are usually very short of money or have money not used in that universe. So, how come they have such a varied and expensive wardrobe?
Answer: They could go to an ATM and withdraw money from the account of that universe's double or, depending on how long they're stuck in whatever dimension they're in, they could do some odd jobs for some extra cash.