Following his Bradshaw's handbook, Michael examines the nation's hidden defences against potential invaders, beginning in the port of Newhaven. Detouring north to Balcombe, he interrupts his journey to appreciate two magnificent engineering achievements - the Ouse Valley Viaduct and the Clayton Tunnel - and learns of a gruesome murder. High on top of a favourite Victorian beauty spot, Michael learns how trains once brought hordes of day trippers here to walk and fly kites. Michael ends this leg of his journey in Worthing, where he finds a novel way to pick tomatoes.