'Project Runway' Sneak Peek: It's Time for the Unconventional Challenge (Exclusive Videos)

Meanwhile, the designers go crazy over guest judge Bette Midler in these exclusive clips from Thursday night's episode.

It's time for the fan-favorite unconventional challenge on this season of Project Runway.

The designers are tasked with creating garments out of materials found at a flower shop and hardware store in Thursday night's episode of the Lifetime competition.

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Meanwhile, Bette Midler and Man Repeller fashion blogger Leandra Medine are the guest judges.

The Hollywood Reporter has two exclusive clips from Thursday night's episode, one that shows the designers scrambling to pick out their materials and the other revealing their surprise and excitement at finding out Midler will be one of the guest judges.

For her part, Midler quips that the designers look like they are full of "piss and vinegar."

Project Runway airs at 9 p.m. Thursdays on Lifetime.