How my brain tumour helped me understand my Pure character

Pure O is a type of OCD which causes intrusive and disturbing thoughts. Pure is a new Channel 4 drama adapted from Rose Cartwright’s autobiography about living with the condition. Charly Clive plays the main character Marnie, who in the drama has intrusive sexual thoughts. She and the screenwriter Kirsty Swain spoke with Jenni Murray on BBC Radio 4’s Woman’s Hour.