The third series begins with a powerful episode about how our lives can change forever in the blink of an eye.
In a shocking random act of violence, a young woman is knocked to the ground after being punched in the face by a stranger on her way home from work. Lying in the street, she's fighting for her life when Andrew, a passer-by, finds her and calls 999.
A&E doctor Des has worked at King's for over five years and is rarely shocked by what he sees, but when the unidentified young woman arrives in Resus with life-threatening swelling on her brain, the impact is felt by him and the entire department.
Also in Resus is 12-year-old Tom. He was hit by a car on his way home from school and airlifted to King's by HEMS, the helicopter emergency medics.
His mum Anna faces an agonising wait as A&E Consultant Emer assesses the extent of the damage to her son's brain.
Meanwhile, 90-year-old ex-circus performer Frank is in A&E after collapsing at home.
News of his colourful past - including training bears and lifting horses - quickly travels amongst the staff as they try to determine what brought him to King's.
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