Dame Julie Walters narrates as, while COVID travel restrictions begin to ease, cameras continue to explore behind the scenes at the massive transport hub, giving audiences an exclusive look at how one of the world's most popular airports handles a worldwide pandemic.

Filmed over the last 18 months, with passengers trickling back into an airport dealing with new and ever-changing challenges, it's still business as usual at Britain's busiest airport.

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.