Clearly this is Casablanca, but I don't think any of the writers or producers thought they were pulling a fast one on the audience. The junk shop guy is Ferrari, the idiot from SGU is Victor Laszlo, the blond lady is Ilsa, Fillion is Rick, the guy in the red concierge coat is Major Strasser, and the Russian lady is Captain Renault - it even ends with Rick and Renault walking off together as Laszlo and Ilsa escape on an aircraft.
I don't think this is a rip off though. I think this as the result of a bet.
In 1996, a shot for shot remake of Casablanca was made called "Barb Wire" - it was futuristic and had a sci-fi type underpinning, and it sucked. By the time this show would have been written and pitched, Barb Wire would have been on the light night cable repeat circuit for so long it would have become a joke to the writers of this show. And this episode would have been born out of an innocent conversation like this:
"What did you do last night?"
"Watched Barb Wire again, then fell asleep on the couch."
"Yeah that movie sucked, I bet we could do a sci-fi adaptation of Casablanca that is better than that movie, and for a tenth of the cost!"
"I don't know...."
And an episode is born.
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