With the NHS under continued strain, cameras return to Imperial College Healthcare NHS Trust in London to witness the extraordinary challenges faced by doctors and hospital staff on a daily basis.

Series two of the acclaimed documentary begins with a harrowing episode as St Mary’s Hospital deals with those injured in the terror attack on Westminster Bridge on 22 March.

Within minutes of the incident staff  have implemented the Trust’s Major Incident Protocol, which sees the hospital put on lockdown and specialist trauma teams in A&E ready to receive patients, including French schoolchildren and a British man who needs urgent surgery to save his leg.