Sheridan Smith stars in this British comedy adapted from Jo Brand's novel. Set in the 1980s, the film follows Gina (Smith), a young mother living with her husband Keith (Mark Addy) and her daughter Alice (Ella Hunt). Suffering from De Clerambault Syndrome, a delusional disorder which causes her to read secret meanings into ordinary conversations and believe that the people she meets are in love with her, Gina finds it increasingly difficult to provide a stable environment for Alice growing up.

Things soon begin to deteriorate as Gina develops an obsession with a local weatherman and is admitted to a psychiatric hospital, a move which forces Alice to go to extreme lengths to try and reconnect with her mum.