For generations, Britain's docks in cities like Liverpool, London and Cardiff were our commercial portals to the world but, as Timeshift shows, they were so much more. Docks were gateways for the arrival of new sounds, styles and cultures to the British Isles. But the docks have also been in the front line of traumatic economic changes that have forced their transformation in the 21st century into clean, contemporary hubs for leisure and the arts. Narrated by Sue Johnston.