'Project Runway' Designer Gets Emotional After Harsh Critique (Exclusive Video)

It isn't Helen Castillo's week on Project Runway.

The designer gets a harsh critique from judges Heidi Klum, Nina Garcia, Zac Posen and guest Eric Daman, an award-winning costume designer whose credits include Gossip Girl, in Thursday's episode, titled "Million Dollar Runway."

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For the challenge, the contestants are tasked with creating designs inspired by more than $30 million worth of precious jewels.

When it comes time for Castillo's critique, the designer admits that she has never made cups before and wanted to try something new -- which didn't sit well with Klum, who says she's always surprised to hear that Project Runway competitors would choose to do something they've never done before during a challenge.

"I am boob-obsessed, but you want to have beautiful cleavage -- and you have your beautiful necklace -- they look pretty bad," Klum says of the dress. "You just bit off too much."

Klum also critiques the construction of the ruching on the model's posterior.

"The hem was off, the fabric was the wrong choice," Posen chimes in, while Garcia adds, "There are so many imperfections that it really distracts from the jewels. The design of it is interesting, but you didn't deliver on it."

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Following the critique, Castillo breaks down in tears. Meanwhile, fellow designer Sandro Masmanidi also gets emotional and comes to her defense. Watch the clip, which is exclusive to The Hollywood Reporter, above.

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