In the play her activity is described in a famous speech by Mercutio written originally in prose and often adapted into iambic pentameter , in which she is described as a miniature creature who drives her chariot into the noses and into the brains of sleeping people to compel them to experience dreams of wish-fulfillment .
In the play she is described by Mercutio as a tiny creature who drives a chariot across the faces of people while they are asleep , causing them to dream of their wishes coming true .