In Bristol, pedestrian 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 to remove part of her skull. Christy now faces months of rehabilitation, including a further operation to replace the missing part of her skull.

After being run over by a forklift truck, doctors fear lorry driver Peter has sustained life-changing crush injuries as he cannot move his legs. Concerned he may be bleeding internally, the medical team bind his lower body to keep him rigid. Once in hospital, scans reveal a pelvic fracture. Peter's legs have suffered extensive soft tissue damage which will take some time to heal.

In London, back-seat passenger Jaqueline is involved in serious road traffic collision. Having sustained a severe open skull fracture to her forehead, Jaqueline begins to lose consciousness and clinicians suspect she may be bleeding in her brain. She is rushed to a major trauma centre for emergency scans. Doctors discover the bones of her skull and face have been smashed inwards and require reconstruction by specialist maxillofacial surgeons.

Michael collapses at work with a suspected cardiac arrest. Doctors and paramedics must try to work out whether a problem with his heart or a brain haemorrhage caused the collapse.

In Newcastle, young mother Gidia is rushed to hospital with multiple stab wounds to her neck and chest. Doctors explore the severity of the knife wounds with scans before sending her for emergency surgery to repair them.

In Durham, cyclist Ben is involved in a collision with a bus and is brought to Newcastle's major trauma centre with major internal bleeding.