At the Lake District base of the Great North Air Ambulance, the crew is alerted to an emergency by Mountain Rescue. A lone walker is not only injured, but has also been stranded for hours high on an isolated mountain. Meanwhile, not one, but two motocross bikers are seriously injured during an event on a remote part of the Pennines. Every year the helicopter crews embark on hundreds of missions to save seriously injured people stranded in remote locations, miles from the nearest road. These are places only the air ambulance can reach. But for the pilots, landing their helicopters on steep and rocky terrain can be the biggest challenge of all - and in this episode, the pilots of the Great North Air Ambulance are tested to their limits.