|For the myth in GTA San Andreas, see Clowns (GTA SA).|
In the mission Grass Roots, Trevor meets Barry at a makeshift table in Legion Square, where he is trying to raise awareness about the legalization of marijuana. Barry insists that Trevor tries some of his weed, and after much debate, Trevor finally gives in and takes a drag of his weed. Trevor's mind and vision blur, and he begins to hallucinate that a large group of clowns begin appearing around him. An automatic shotgun appears in his hands, and he begins killing the clowns and destroying the Clown Vans that continuously generate more clowns. After killing all the clowns, his vision becomes clear again and his hallucination sequence ends. He storms off angrily, and it becomes apparent to him that the drug, that Barry gave him, was clearly not marijuana.
During the mission, Trevor makes many angry remarks, strongly hinting that he has a fear of clowns (Coulrophobia). It is presumed that Trevor had an irrational fear of clowns, since he was a child, thus explaining his hallucination involving clowns trying to attack him. Michael De Santa has a similar hallucination in his own version of the Grass Roots mission, only this time his hallucination involves Aliens.The clowns do not appear outside of this mission, and the Clown Van cannot be obtained by regular means unless the player uses mods to make it spawn.