The stakes are stiletto high for another batch of daring designers aspiring to, as style mentor Tim Gunn requests, "make it work" in Season 4 of the popular reality-competition series hosted by supermodel Heidi Klum. Standout contestants include Chris March, a sensitive costume designer with a memorable laugh; Christian Siriano, outlandish in both attitude and fashion sense; and Kathleen "Sweet P" Vaughn, whose subdued designs belie her tattooed exterior. Sarah Jessica Parker, Donna Karan, Roberto Cavalli and Victoria Beckham are among the guest judges joining series regulars Klum, Michael Kors and Nina Garcia to critique and eliminate the clothiers. Tiki Barber appears in an episode that finds the designers crafting a look for the former NFL player to wear on air. Other memorable challenges include using candy to make a garment, refitting an outfit for women who have lost weight, and updating outdated sportswear.