On Saturday 22 May 1937 the Habana - a former luxury liner built to carry 400 passengers - docked at Southampton. On board were 4,000 children who were escaping the horrors of the Spanish Civil War. To this day they remain the single largest influx of refugees ever to enter this country, yet their story is virtually unknown. Now, using extensive recordings made by presenter Adrian Bell as he scoured the country for surviving refugees and those who helped them, the story of the forgotten 4,000 is finally told.