In this four-part documentary series, leading Hollywood actors undertake a fascinating journey into their family's past by re-tracing the footsteps of their grandparents during World War Two. We follow the moving, personal stories of Helena Bonham Carter, Mark Rylance, Kristin Scott Thomas, and Carey Mulligan as they travel to historic locations, from the beaches of Dunkirk to prisoner of war camps in Asia, to learn about the war their grandparents experienced.