Mega-stylist to the stars, Karla Welch is here to guest-mentor the designers and she's got a job for them – dress her client: the one and only Karlie Kloss! Karla's got a twist though, the materials used to design the look will be donated clothing from a local Goodwill, making this Project Runway's first upcycling challenge. The designers will need to be resourceful, sustainable, and fast because it's also their first one day challenge. One designer's dreams will come true with the chance to dress a supermodel while another will be all out of second chances in this second-hand challenge.

In this week's challenge, the designers are given a chance to think about their family history and channel those stories and emotions into a look of their choosing. The stakes are high in this one day challenge, as the designers need to face and embrace who they are in order to succeed. Luckily for the designers, there's a surprise early on that will help boost their chances for success in this Flash Sale Challenge!