Though the whiteboard says "Clowns", only one clown is seen, at the end of the film. Despite his status as monster, he has no outwardly creepy features, bearing the stereotypical appearance of a clown: poofy red hair, red nose, colorful makeup, and baggy, multi-colored clothes with frilly trim. Due to his colourful, friendly, and cute appearance, it may enable him to visit densely populated areas without scaring people, and unwary victims could easily mistake him for a regular circus clown and not suspect his true violent nature. His joyous pretense is perhaps his most deadly weapon of all. He dispatches of victims by stabbing them with a long, curved knife while giggling and laughing hysterically. Earlier in the film, when told that that Electrical had placed their bet, Hadley stated "Did you see who they picked? They're practically giving their money away." This seems to suggest that the Clowns are rarely ever summoned to the Cabin.
Before the Purge, he is first seen in his glass cube.
During the Purge, he is seen mocking Hadley from one of the monitors. Later he is seen stabbing an employee of the facility in the stomach, before turning to face a female security guard. The guard shot the clown three times in the chest, only for the clown to shrug off the shots and attack her, presumably killing her.
Drew Goddard has said that the fortune teller machine in the basement is used to summon him/them.
The Cabin in the Woods attraction at Universal Studios during Halloween features a clown monster called Jack, as well as a Clown.
The "Evil Clown" is a classic horror trope which stems from the common real-life fear of clowns, or Coulrophobia, as well as the infamous serial killer John Wayne Gacy. Other famous fictional examples include:
- Joker from DC Comics
- The Penguin's minions from Batman Returns.
- Killer Klowns from Outer Space
- Pennywise from Stephen King's It
- The Evil Clown Doll from Poltergeist
- Killjoy from the movie franchise of the same name.
- Spaulding from House of 1000 Corpses and The Devil's Rejects.
- Zombieland where the protagonist has Coulrophobia (fear of clowns) and has to meet a zombie clown during the film.
- Many movies such as Clownhouse, Drive Thru, The Funhouse, Amusement, Circus Of Fear,
- Stitches from the horror movie of the same name.
- Twisty the Clown from American Horror Story: Freak Show.
- Needles Kane, better known as Sweet Tooth from the videogame Twisted Metal
- Murder the Clown from the Goosebumps franchise.