"The Dreamer Trilogy" is a series of young adult fantasy novels written by Maggie Stiefvater. The trilogy consists of three books: The Raven Boys, The Dream Thieves, and Blue Lily, Lily Blue. The story follows Blue Sargent, a girl from a family of psychics, and her interactions with a group of boys from the nearby Aglionby Academy who are searching for a legendary Welsh king. The series explores themes of friendship, destiny, and the power of dreams. It combines elements of magic and adventure, as the characters navigate their relationships and uncover secrets about themselves and the world around them. The trilogy is known for its lyrical writing and rich character development.