Popsugar Celebrity Halloween Costumes 2019 100+ of the Best Celebrity Halloween Costumes of All Time 350+ Celebrity Halloween Costumes That Are Hilarious, Spooky, and Downright Stylish 10 October 2019 by Lauren Turner View On One Page Photo 226 of 243 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 226 Lily Allen Lily Allen dressed up as an alien for the 2013 UNICEF UK Halloween Ball in London. Previous Next Start Slideshow Halloween Costumes 2019Couple Halloween CostumesPop Culture Halloween CostumesCelebrity Halloween CostumesHalloween CostumesHalloween