"The Head on the Door" is a novel by Julian Barnes, published in 1984. It is a part of the Duffy series, featuring the character Detective Inspector Duffy. The story revolves around a murder investigation that takes place in a small English town, exploring themes of identity and the complexities of human relationships. The narrative is characterized by its intricate plot and rich character development. As Duffy delves into the case, he uncovers secrets and lies that challenge his understanding of the people involved. The novel combines elements of mystery and psychological insight, making it a compelling read for fans of the genre.