The Hills' villain-in-chief, Spencer Pratt, and plastic girlfriend Heidi Montag have fully refueled their long-standing feud with Lauren Conrad.

During a taping for Tuesday's upcoming episode of The Tyra Banks Show, Spencer Pratt says he is "100 percent" sure there is, or at least was, a Lauren Conrad sex tape:

"I know for 100 percent fact it did exist. 1,000 percent!"

Tyra Banks asked if Spencer Pratt had actually seen it.

"I would never watch that!" Pratt replied. "I would rather throw up... but I know for a fact, and I would take a lie detector test."

The alleged Lauren Conrad sex tape supposedly co-starred her boyfriend at the time, Jason Wahler, who recently got his own show, 22 and Taken.

Heidi Montag â€" who appeared alongside Spencer Pratt on the show â€" is also claiming the tape was "not a rumor. From what I have heard from confirmed sources, her ex-boyfriend was going around trying to sell it."

She said she hasn't seen it either, shockingly.

What do you think? Is there, or was there a Lauren Conrad sex tape? Or are Spencer and Heidi just bringing this up again for publicity?

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.