One Direction's Zayn Malik keeps it simple dressed as a ghost. Wooooooohhh! This image appears in the gallery:29 Incredible Celebrity Halloween Costumes: The Spookiest Outfit Ideas 15. One Direction's Zayn Malik keeps it simple dressed as a ghost. Wooooooohhh! Picture: Goff/thinkstock 29 images See the full gallery: 29 Incredible Celebrity Halloween Costumes: The Spookiest Outfit Ideas