Moped rider Martin is fighting for his life after a collision with a lorry in London. Doctors are concerned have may have severe head and spinal injuries after the wheel of the lorry pressed against his head.

In Bristol, Christy is hit by a car. Doctors suspect she may have bruising to the front and back of her brain and give her an emergency roadside anaesthetic. In hospital, her brain begins to swell rapidly and she undergoes an emergency operation.

Fitness trainer Dusan is in critical condition after being hit by a bus. In hospital, he is declared a code red and receives immediate blood transfusions.

Michael collapses at work with a suspected cardiac arrest. Doctors must work out whether issues with his heart or a brain haemorrhage caused the collapse.