大象传媒

Dom Littlewood goes behind the scenes at some of Britain鈥檚 most secure institutions to see how they keep us and the country safe. On today鈥檚 show, Dom visits Britain鈥檚 busiest airport, Heathrow, to see how passport control operates. He sees how police horses are trained, then joins the South Wales Mounted Police as they patrol Cardiff鈥檚 streets to keep over 60,000 music fans safe at an Ed Sheeran gig.