Lifetime has revealed the identities of the 15 designers who will be competing in Under the Gunn, a new Project Runway spinoff starring Runway mentor Tim Gunn, which premieres tonight at 9PM ET/PT.

In addition, the network announced whom will serve as guest judges throughout the season.

Reality TV star and model Heidi Klum, actor Neil Patrick Harris, musician Macklemore, actor Jaimie Alexander, actress Zoey Deutch, actress and former Dancing with the Stars finalist Zendaya Coleman, designer Georgina Chapman, designer Trina Turk, costumer Wendy Partridge, and actress Sarah Hyland will all be making an appearance on the new show.

Lifetime had previously announced Under the Gunn's regular judges will be designer Rachel Roy, celebrity stylist Jen Rade, and Marie Claire Senior Fashion Editor Zanna Roberts Rassi.

Gunn has been a mentor on Project Runway since its first season debuted in 2004.

Project Runway alumni Mondo Guerra, Anya Ayoung-Chee and Nick Verreos will serve as the competition's mentors and each be responsible for choosing a small team of 15 up-and-coming designers to "manage, coach, cheerlead and, when necessary, knock down with tough love in order to lead them to runway success," according to the network.

Klum has hosted and judged Project Runway since its inaugural season premiered. Verreos appeared on the second season of Project Runway in 2005. Guerra finished as the runner-up on Project Runway's eighth season in 2010 and then went on to win Project Runway: All-Stars last year. Ayoung-Chee won the ninth season of the series in 2011.

The winner of Under the Gunn will receive a cash prize of $100,000; a sewing and embroidery studio; an all-expense paid trip to Paris; Blowpro styling products; the opportunity to design the uniform for Benefit Cosmetics' field team members and unveil the ensemble during a national press conference in New York City; a fashion spread in Marie Claire magazine; a one-year position as guest editor for Marie Claire; a 2014 Lexus vehicle; and the opportunity to design a collection sold exclusively at Francesca's.

The same production companies behind Project Runway -- The Weinstein Company and Bunim/Murray Productions -- will also be producing Under the Gunn. Gunn, Bob Weinstein, Harvey Weinstein, Meryl Poster, Barbara Schneeweiss, Jonathan Murray, Sara Rea, Teri Weidman, Eli Lehrer, Mary Donahue, and David Hillman will be serving as executive producers for the new series.

The 15 designers who will be competing on Under the Gunn are as follows:

- Amy Sim, a 53-year-old from Portland, OR

- Asha Daniels, a 25-year-old from Cincinnati, OH

- Blake Smith, a 25-year-old from Hoboken, NJ

- Brady Lange, a 29-year-old from Portland, OR

- Camilia X Castillo, a 47-year-old from Caracas, Venezuela

- Isabelle Donola, a 33-year-old from New York, NY

- Melissa Grimes, a 29-year-old from Birmingham, AL

- Michelle Uberreste, a 29-year-old from Burbank, CA 

- Natalia Fedner, a 30-year-old from West Hollywood, CA

- Nicholas Komor, a 26-year-old from Atlanta, GA

- Oscar Lopez, a 40-year-old from Coral Gables, FL

- Rey Ortiz, a 32-year-old from Anasco, Puerto Rico

- Sam Donovan, a 23-year-old from Ashland, MA

- Shan Keith, a 33-year-old from St. Louis, MO

- Stephanie Ohnmacht, a 37-year-old from Denver, CO