This episode goes behind the scenes of travel's new normal - the test and trace. Passenger numbers may be down by 77%, but deciphering the protocols of all 206 countries that Heathrow fly to is more complicated than navigating Spaghetti Junction in rush hour.On the frontline is Joel, the manager of Heathrow's testing centre, who leads the charge in trying to reduce passenger stress and makes sure that everyone gets the right test for the right country –  tonight he's dealing with a particularly irate Israeli family. Outside on the airfield, we're back with the airport's favourite moustache wearer – Airside Ian, who has a new weapon to test out on the ever-encroaching wildlife. Things are heating up in immigration, where Passenger Experience Manager Suki has an emergency on his hands, and Security Officer Estefania gets an unexpected make-over.