"Crossing the Line" is the 137th episode of Casualty and the ninth episode of the 9th series.
Teenager Chloe visits her boyfriend Ken but he has been warned off her by his employer Debbie, a friend of Chloe's mother Fiona. A woman named Shirley has a violent argument with her boyfriend Mark before taking a minibus full of elderly people out; distracted, she runs over Chloe. Chloe believes she is pregnant and gets Adam to give her a test in front of Fiona, but it turns out to be negative. Chloe reveals she knows Fiona and Debbie are lovers and the three of them begin to get on better. Kate realises Shirley has PMT, having stopped taking the pill because she was insecure about Mark having children from an earlier relationship, and Mark is horrified to learn she was trying to get pregnant. Young boy Danny finds his father Russell has overdosed before he leaves for school and calls the ambulance. He tells the staff his mother died in a climbing accident and he has no other family but in fact his maternal grandmother Maureen is still alive: She blames Russell for the accident, as does Russell himself. Russell and Maureen agree Danny should stay with Maureen until Russell gets over his depression. Glen and Emma have separated and Emma asks Adam to look after Jessica. Rachel begins counselling. Ash is charged with ABH and the police interview the staff; after pressing from Jude, Matt tells them that he heard Hitchens threatens Ash and agrees to give evidence.