Timeshift explores the lost world of coal mining and the extraordinarily rich social and cultural lives of those who worked in what was once Britain's most important industry. It's a story told through a largely forgotten film archive that movingly documents the final years of coal's heyday from the 1940s to the 1980s. One priceless piece of footage features a ballet performance by tutu-wearing colliers. Featuring contributions from those who worked underground, those who lived in the pit villages, those who filmed them at work and at play and those - like Billy Elliot writer Lee Hall - who have been inspired by what made coalfield culture so unique.