16 new designers arrive in NYC with big dreams and a homework assignment: bring a garment that best represents their aesthetic. Upon arrival, they learn that for their first challenge they will have to create a companion piece to that look, and they will only have one day before they are presenting on the biggest stage in Project Runway history: the middle of Times Square!

The designers participate in the always-anticipated Unconventional Materials Challenge of the season. This time around, the designers are tasked with making a garment entirely from items that are found in Dylan's Candy Bar.

The designers are broken into teams of two, where they are tasked to design a red carpet look to be worn at the Emmys. Each team is assigned a client to design for, and this client is one of several past contestants on Project Runway. Each outfit is also inspired by a different color Lexus, which serves as their mode of transportation in the beginning of this episode.

For the Michael Kors Challenge, the designers are tasked with making an outfit for a woman on the go-something chic and stylish but wearable enough to last throughout the entire day. Also, the designers are left in a state of confusion as two of their fellow competitors abruptly decide to leave Project Runway.

In the Marie Claire Challenge, the designers are once again split off into teams to design a fashion capsule collection for the new magazine Marie Claire at Work. The teams also must direct a fashion shoot for their collection, which is also part of the criteria they are judged on for this challenge.

In a challenge for L'Oreal, the designers team up with clients whose friends or loved ones are in desperate need of a makeover. The designers must consult and work with their clients to give them a new and flattering look that is also conducive to their lifestyle.

For the Lord and Taylor Challenge, the designers receive the opportunity to design a look for a capsule collection that celebrates ten seasons of Project Runway. If chosen as the winner, their look would join the ranks of many former Project Runway designers and winners, and it would be manufactured and sold at Lord and Taylor.

For this challenge, the designers divided into teams of three, and they must raise their own shopping money by selling t-shirts and other designs on the streets of NYC. Once they have raised their money, they have to design a two-piece fall collection, and one look must include a piece of outerwear.

For the HP Challenge, the designers must create their own textile and design a look that is representative of their heritage. They are surprised when a member of their family comes for a surprise visit and helps them with their inspiration.

The designers are treated to a show at Radio City Music Hall, where they learn that they will be designing an outfit for the world-famous Rockettes to wear in an upcoming performance.

For Heidi's challenge, the designers arrive at Babies R Us where they learn that they will be designing an outfit for their youngest clients yet-babies! Heidi throws another twist at the designers; they also must create a complementary look for the baby's mom to wear.

As the designers face their final challenge before Mercedes Benz Fashion Week, they are tasked with their most difficult and creative challenge yet: making an avant-garde look inspired by L'Oreal's new line of makeup called "Electric Fantasie".

Weak and weary from their journey, the few designers left say goodbye to NYC and return to their respective hometowns to begin working on their final collections. Tim Gunn travels to visit the designers and assess their progress. In the end, all four remaining designers must present their three best pieces to the judging panel, as the judges are left to decide who will move on.

It's the moment of truth for the remaining designers as they each present their final collections to an eager audience at Mercedes Benz Fashion Week. One designer is named the winner of Project Runway Season 10, and the rest are unfortunately out.