Watch Britain's Busiest Airport: Heathrow Season 2 Online

Heavy fog throws Heathrow into turmoil and new terminal manager Callum is faced with hundreds of angry and stranded passengers stuck overnight at the airport, while visibility has dropped to less than 100m on the airfield and safety officer Chris is forced to marshal planes. Manager Nilam reveals the secrets of one of Heathrow's most exclusive first-class lounges and dispatcher James and his team hunt around the terminal for late passengers for a flight to Pakistan.