Popsugar Entertainment Halloween Costumes 2021 Only Murders in the Building Halloween Costume Ideas Only Murders in the Building Is About to Be One of the Biggest Group Costumes This Halloween 30 September 2021 by Kelsie Gibson View On One Page Photo 7 of 7 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 7 Detective Williams on Only Murders in the Building Halloween Costume What to wear: Detective Williams's outfit is pretty simple. All you need is a dark v-neck shirt, a pair of dark wash jeans, a blazer, and a badge. Previous Next Start Slideshow Halloween Costumes 2021Only Murders In The BuildingStreamingHuluHalloween Costumes For MenGroup Halloween CostumesHalloween Costumes For WomenPop Culture Halloween CostumesHalloween CostumesHalloween