Chain Reaction (series 4)

 was the first episode of Series 4 and the 41st episode overall.

Plot
Lucy Perry treats a young woman with cervical cancer before being called out with Cyril to a road crash. A car has collided with a lorry carrying drums of chemicals and a second car has rolled over killing the driver. A young girl hitchiker is thrown through the car windscreen and has head injuries. The lorry driver needs a chest drain which Lucy performs at the roadside. A policeman is burned by a pool of acid and dies in CRASH as his wife arrives to see him.