In April 2011, four soldiers - each a veteran of recent conflicts, who suffered devastating injuries in the line of duty - set out on an extraordinary challenge: a two-hundred mile trek, unsupported, to the North Pole.

Joined by patron Prince Harry, the charity founders, a polar guide and a film crew, the team achieved their goal despite facing hurdles an able-bodied athlete would baulk at, and having seen their resilience tested to the limit. They returned with a story that proves strength of mind can be every bit as powerful as strength of body, and as an inspiration to us all.