The document describes the casting choices for a film's opening sequence. Charlotte Heavey was cast as the main character Amelia Rose, a 15-year-old schoolgirl, because she has drama experience. Ellen Jenkins and Carys Jones, both also age 15, were cast as Amelia's school friends Annabelle and play supporting roles also wearing their school uniforms. Jessica Heavey was cast as Amelia's mother for her acting skills. Cameron Whitehead was chosen to play the stalker for his build and ability to appear bold in dark clothing. Lily Penfold and Georgia Claydon wear casual clothes for their weekend scenes with Charlotte.