For tonight’s Halloween episode of the fairy tale-inspired Grimm on NBC, the show re-creates the Mexican folklore “La Llorona,” dating back to the 16th century. The legend tells the story of The Weeping Woman, who kills her children so she can be with the man she loves. When he rejects her, she throws herself into a lake and is forced to roam Earth as a ghost for all eternity. To re-create the “alive” version of the woman (played by Angela Alvarado), costume designer Alexandra Welker turned to Alexander McQueen for inspiration, and hand-designed the look using Marc Jacobs cotton. “I went to see Savage Beauty, the retrospective at The Met last year, and [the late designer] worked a lot with beautiful layering, fluttering chiffon,” Welker told InStyle.com. “I wanted to work with materials that would float, have movement, and look angelic.” For the “undead” version, she wanted something much darker. “For the tattered version, we dyed everything to make it look like it was stained with 100 years of tea or cigarette smoke,” Welker told InStyle.com. She also ripped the sleeves so you can see her “moldy-looking arms” while the character thrashes in the water. “I wanted the effect that the cloth had just completely rotted,” Welker added. Tune in at 9/8c tonight on NBC to see her costume work in action.