Alan gets under the skin of the much misunderstood Neanderthal man, examines relics from the past and discovers that an ice sheet covering most of Britain stopped at London's Finchley Road tube station. Armed with a geologist's microphone, he eavesdrops on the groans of a Norwegian glacier. In Trafalgar Square, 19th century builders found an extraordinary collection of bones, including those of hippos, hyenas and lions, demonstrating that the Ice Age was not unrelentingly cold.