The foursome won the opportunity to create a collection to showcase at New York Fashion Week on Thursday night's episode of the Lifetime competition, which also saw designer April sent home by the judges.
Heidi had told all five designers that they were "very talented" but there was only room for four at Fashion Week, and only three would have the chance to compete as a finalist.
The episode opened with the remaining five designers spending the night at a luxury hotel in Manhattan and reflecting on their journey in the competition. Gretchen said that she was happy to make it so far but was desperate to reach Fashion Week ("It is the essence of why I'm a designer"); Andy said that it had been a "crash course of getting to know who you are and sticking by who you are"; Michael C said the show changes you because you learn how people view you and your designs; April said it had made her a "stronger person and designer"; Mondo said the show had "set [him] free".
The next morning the designers met Tim Gunn and Mayor Bloomberg, who was on hand to reveal this week's challenge: they had to choose a New York City landmark to provide inspiration for their final runway look. They also received $500 (the biggest budget of the season).
Michael C chose the Statue of Liberty and wanted a dress that was structured and draped; April chose the Brooklyn Bridge and was inspired by the construction and shapes; Mondo also chose the Brooklyn Bridge but drew his influence from the bars, cabling and cars; Andy visited Central Park where he focused on the organic lines he saw; while Gretchen travelled to the Lower East Side and used the worn brickwork as the focus on her design.
Back at the workroom on day one, an exhausted Mondo decided to take a nap while the rest of the designers worked. Michael C was worried his design was playing too safe, while Gretchen thought Andy's black cocktail dress was like something a madam would wear. The next day Andy admitted that he had gone back and forth with his design but was sticking to it. Elsewhere, Michael began working on pleating to replicate the base of the Statue and the brickwork because he didn't want the judges to think he was playing it safe. Mondo decided to take the plunge and cut his yellow sequin material (to represent cabs) but decided it was unworkable and he could still show his point of view in black-and-white.
Tim then arrived to give the designers' feedback and supported Mondo's decision to scrap the yellow fabric, while Michael C privately praised Mondo's skill: "I have never seen so much creativity in someone as I do in Mondo and [he's] so classy." April explained she was doing a black abstract coat dress with one complete sleeve and one open-shouldered tube sleeve, while Tim told Michael C he should look at the other designers and question if they are being more ambitious, adding that the pleats looked like a "tortured mess". Tim warned Andy not to make his black cocktail dress "too slutty" or something a Real Housewife Of New Jersey would wear; while he advised Gretchen that although she wanted to stay true to herself with her brick-coloured skirt and cropped leather jacket, she needed to keep in mind her customer.
Season four winner Christian Siriano joined Heidi, Michael and Nina for the runway.
The panel loved his long black and flowing asymmetrical dress with a slit to the thigh. "You wanted a show-stopper and you got a show-stopper!" said Michael, who also praised the "beautiful cut and draping". Nina was particularly impressed with the fit of the dress and its movement, and although Christian thought the slit was too high, Heidi said she loved it and wanted to wear the gown.
The judges were not particularly impressed by Gretchen's separates combination of brick-coloured skirt, cream satin top and leather cropped jacket. Michael said she had lost her steam and the model had no vibe: "She looks rock and roll secretarial." Nina was also confused, saying it was like another designer had taken over Gretchen's body. Gretchen admitted she was exhausted and tiring of the challenges, although Heidi pointed out the designers had freedom to do what they wanted in this challenge.
The panel liked his black, wet-look cocktail dress with a cut-out back although Michael couldn't see the Central Park inspiration, pointing out it was "more like Blade Runner or a Robert Palmer video girl from the '80s". Heidi liked the lines because they flattered the body, while Nina called it the "perfect little black dress for an edgy girl" and Christian praised the accessorizing.
Michael loved the architectural inspiration of the design (a mixed textile and patterned short dress in black-and-white) and the fact it was "still full of joy and Mondo" despite being neutral coloured. Nina said he never lacked ideas and called it a "really phenomenal dress". Christian thought it was "very chic" and appreciated the mixture of textiles, however Heidi admitted that she would have loved to see something different from him.
Michael thought her long black dress was very similar to previous designs and compared the look to a "pregnant witch". Heidi questioned why she hadn't used this challenge to incorporate colour, to which April said she liked "drama and dark elegance". Heidi said she should have stepped outside her comfort zone and surprised them. Nina agreed and admitted she didn't know if April had any range. Christian liked the cut of the dress and pointed out the model looked like April.
Michael C, Mondo, Andy and Gretchen won a place in the final four. April was sent home because although her dress had "interesting design elements", the panel felt they had seen a similar product "many, many times before".
"I'm really surprised that they won't give me a shot at Fashion Week because I feel like I am a strong designer," said April immediately afterwards. "I'm kind of shocked I guess." Tim told her to be proud of herself and pointed out that at 21 years old she was the youngest designer and is "just at the threshold of a staggering career".
"I'm proud of how far I got, that's for sure," added April. "It just sucks I had to be the one to go right before Fashion Week. It's like, 'Almost there, bam! Not there!' It really is bittersweet but I am looking ahead. I don't ever look back so I'll be OK, for sure."
Project Runway continues next Thursday at 9/8c on Lifetime
> Click here to read our interview with April