Both singers previously have been cast in Syfy originals but never have appeared together.
The film, which features the pair brawling at a party and then in a swamp, will start filming this month and is slated to air next year.
“They loved the idea of taking this perceived rivalry and having some fun with it,” Executive Vice President Thomas Vitale said. “The catfight on Dynasty was a seminal TV moment and it’s time to re-create that for a new generation.”
“I know that pop culture fanatics have been dying for Tiffany and me to collaborate for the past 24 years!” said Deborah “Debbie” Gibson in a statement. “What better way to do it than by battling each other in a campy romp through the Everglades?”
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