"The Kindness of Strangers" is the 831st episode of Casualty and the 8th episode of the 27th series.
Zoe is struggling with the administrative side of her new job as clinical lead, so when a teenage girl is rushed in following a car accident, she spots an opportunity to do what she does best - treat patients. The youngster is covered in scars clearly caused by previous injuries, but in the medic's eagerness to help, she misses a vital clue. Big Mac is back at work after his heart attack, irritated that the department has functioned perfectly well without him. But when he tries to help a patient, his good intentions are questioned by Dylan.