In a whirlwind challenge, designers have only four hours to craft fresh designs from thrifted pieces. Internet personality Emma Chamberlain guest judges.

The designers pair up to wow Balmain's Olivier Rousteing with coordinated looks, and learn that creative chemistry can make or break a collaboration.

Riffing on the theme of camp, the designers create over-the-top ensembles worthy of a Met Gala red carpet for guest judge Bella Hadid.

Pairs of contestants dive into a rapid-fire swimwear challenge to create two suits that will impress model and designer Candice Swanepoel.

Tan and Gigi fire up their time machine, sending designers to past decades to find retro inspiration for contemporary looks. Hailey Bieber judges.

The final four pull out all the stops to design two-in-one pieces that can transform in an instant, with actor Ashley Park of "Emily in Paris" judging.

Three finalists have a chance to showcase their artistry and talent with a full collection of new styles — but only one can walk off the runway a winner.