On 14 August 1943, Adam Hart's great-grandfather Frank Griffiths took off from RAF Tempsford, the SOE 'Special Duties' airbase in rural England. Frank and his crew were on a secret midnight mission codenamed Operation Pimento, but they were shot down near Annecy in southeast France.

Only Frank survived.

Though seriously injured, Frank felt it was his duty to get back to England to continue the fight against the Nazis. He embarked on a perilous, 1,200-mile, 108-day escape across Europe, via the attic of a brothel, a Frenchwoman's chimney and a Spanish prison cell. Seventy-nine years later, Frank's 22-year-old great-grandson Adam Hart retraced the epic escape through France, Switzerland and Spain. His emotional encounters with descendants of people who'd risked their lives to help his great-grandfather reveal the enduring legacy of Operation Pimento and how we should never forget their sacrifice.

Operation Pimento is not only a riveting true story, but also a vivid account of one young man's journey to discover more about a man he'd never met, but always knew to be a hero.