'Project Runway' Sneak Peek: Thunder From Down Under Stars Heat Things Up (Exclusive Videos)

The designers are tasked with creating outfits for the male performers in what Heidi Klum calls one of her favorite challenges this season.

Project Runway gets a little racy this week.

"It's time to have some fun!" host/judge Heidi Klum exclaims in teasing the challenge to the designers. "This next challenge is, let's just say, probably one of my favorite ones of the season."

The designer soon learn they will be creating outfits for a group of clients who aren't afraid of taking it off. So who are they? None other than the performers of the male review Thunder From Down Under. 

Lifetime promises that judge Nina Garcia is left speechless for the first time in this week's episode. Meanwhile, check out the designers' reactions in these two clips, which are exclusive to The Hollywood Reporter.

Emmy Rossum serves as guest judge on Thursday's episode, which airs at 9 p.m. on Lifetime.