The 'periscopes', installed in Terminals 2 and 5, offer passengers a chance to peer into a 360° world of elvish activity taking place beneath the airport's terminals, with scenes from Santa's Toy Factory, the Department of Wrapping, and the Mail Room – all acted out by Heathrow staff.
The ideation and delivery of the campaign was developed with PR firm Kindred.
The scenes reveal Heathrow's long-held secret: that Santa, like many others around the world, relies on the UK's hub airport to get where he needs to be during the holidays.
The film follows new research by Heathrow which revealed the toughest questions kids under 10 ask their parents in the run-up to Christmas, including: "How does Santa really get to every house in the world?"
Operating at near-capacity, Europe's biggest airport expects 6.5m passengers to go through its doors this month, with 255,133 expected to fly in and out on the busiest day – 20 December – alone.
Elizabeth Hegarty, director of customer relations and service at Heathrow, said: "This experience hopefully provides a little festive fun during their time at the airport – and helps parents to answer curious children's questions."