Travellers face the challengers of transferring in the five-square-mile airport, with 200 gates and four terminals.

Passenger Experience Manager Sue does her best to get a passenger to his connecting flight at Gatwick - 38 miles away.

This episode follows Heathrow staff trying to process 100,000 departing passengers a day, and get their flights away on time. Dispatcher Callie and Ramp Manager Steve have their plans thrown into chaos by a passenger who disappears after checking on to their flight. In Security, Sundeep and his team have to search an unusually dressed traveller, and deal with a man who is unhappy about having his bag searched. Meanwhile, Heathrow’s extradition team ensures police suspects are put on departing flights, while paparazzi photographer Kate is on the lookout for celebrities flying through the airport.

With only one runway and two terminals open, Heathrow's depleted staff are fighting to keep business going. At the helm is King of Customer Service Demi, dishing out help to all those allowed to travel, including tracking down a missing passenger.

It is all things Eastern with the arrival of some special cargo, a potential people trafficker flagged to Border Force, and the polar vortex that battered Britain in March affectionately called the Beast from the East. Also, rookie Ian is back.

Storm Eunice wreaks havoc at Heathrow airport, as staff deal with a deluge of delays and unhappy passengers, and also try to deter debris from hitting the runway.

Terminal 5 receives a very special visitor, leaving Buggy Driver Carlo starstruck. British Airways have a new robot on the airfield and Border Force release the hounds in search of dirty money. Last in the series.

The airport is busy as it is half term with rich Russian kids returning home from British boarding schools, and trouble arrives when the biggest mobile crane stops in the middle of a live airfield.

The Border Force pull over a Ghanaian businessman declaring £114,000 in cash, there is love in the air at the unlikely location of T5 arrivals when a blind date takes place and it is the end of an era on the airfield for chief trainer Simon.

Border Force Bob juggles visas with a circus performer, whilst Security Officer Estefania investigates an oddly shaped object. There's also drama in Terminal 3 for Passenger Experience Manager Harry as he deals with a medical emergency.

The King and Queen of Terminal Two, Demi and Sue, wrestle with a bare chested drunk, and back at immigration Kat and Bob come across a visitor whose reason for entering the UK does not add up.

This episode follows Heathrow staff racing against the clock to process thousands of passengers arriving from 84 different countries. Airside Safety Officer Glenn and his colleagues work closely with Air Traffic Control to keep Heathrow’s two runways open and clear of debris. Meanwhile, staff from the Animal Reception Centre welcome a variety of weird and wonderful animals – from pet ferrets to a wild tiger. Inside the terminals, Heathrow staff deal with passengers including a man who is stuck living at the airport after being deported from Thailand, and a family whose young relatives have got lost in Arrivals.

The airport runs at capacity, and the king and queen of Terminal Two, Sue and Demi, cope with the extra load from a closed Gatwick. Meanwhile, border force Bob is back, doing what he does best, protecting Britain's biggest border.

Passenger experience manager Demi deals with some disgruntled passengers, while check-in attendants Carrie-Anne and Selina tackle broken baggage belts. Elsewhere, Border force worker Bob has to decide whether he should let a young Brazilian student into the UK to visit his brother.

This episode follows Heathrow staff struggling to turn around hundreds of arriving planes, and get them back into the air on time. Cleaners, ground staff and flight crew race to get the world’s biggest passenger plane ready for departure. Meanwhile Heathrow prepares to open a £2bn new terminal, and welcomes a very special royal guest. Airport duty manager Andy is called on to defuse a major international protest, and a team of workers battle the elements as they attempt to resurface the runway overnight in time for the first flight of the morning.

The last super jumbo of the skies, the A380, visits Terminal 3 - elsewhere, passenger numbers are at their highest, there's a dodgy substance in security, and there's also a potential waste disposal issue in a toilet block.

This year is Heathrow's 75th birthday and as it continues to get back on its feet the time has come to open up the last of its closed terminals - Terminal 4.

An arresting episode greets viewers this time as Heathrow's boys in blue dash to the gate. Plus, Queen of Passenger Experience Sue sorts out some gents, whilst out on the airfield, Airside Ian shows off his muscles.

Police detain a passenger whose bag is suspected to contain three firearms. Virgin has a rootin' tootin' launch party for their new route to the live music capital of the world - Austin, Texas.

Boarding passes ready as police mount a special operation across the airport. Plus, a five-star airline tries to make a comeback with its business class, and we go out with the new recruits of the grass cutting team.

Holidays are put on hold as it's the Queen's Jubilee and Heathrow is entertaining a 72-military aircraft flyby 5,500 feet above its runway, and passengers waiting for flights have a ringside view.

Answering the question of whether you could pick up someone else's boarding card and take a trip around the world. Plus, some plane-spotters await a rather rare sight.

It's midnight. Airside Ian checks Heathrow's airfield lights before the onslaught of half term. Drugs Dog Cole protects the Border, while officer Estefania pushes passengers through security with a unique handling method.

Although there may be fewer passengers disrupted by the visit, it's still a huge deal logistically that Heathrow will be welcoming the President of the United States.

At Britain's busiest border, officers Kat and Tracy help a student from India who's arrived with no fixed abode, while on the airfield, Airside Ian is ducking and diving on the runway. Terminal 4 welcomes an exuberant new ambassador.

Heathrow is back in business as holidays take off. A pilot needs help from the police with a very disgruntled passenger, fire engines give a bath to a Boeing triple 7 and new airline Rwandair deals with some very charming travellers.

It's all smells at Heathrow's Terminal 3 with a new restaurant, and Border Force dog Jessie sniffing out thousands of pounds. Meanwhile, Airside Ian is ramping up his crow impersonations, and Demi prevents a cardiologist having a heart attack.

A five-star airline gives a top tier performance all about baggage. Plus, Border Force Rob deals with a frozen chicken trying to enter the country, and there's a surprise for passengers flying across to Heathrow's number one European destination.

It's a day like no other, with one octogenarian forcing herself into the country under the watchful eye of Passenger Experience Guru Demi. Terminal 4 turns blue, and airside Hugh has a potential environmental mess on his hands.

In the coloured lanes of customs and excise, we rummage through carry-on luggage on the lookout for secret stashes. Virgin Atlantic's punctuality record is put in jeopardy by a captain's bottle of water, and there is love, actually in the air.

At Heathrow's Terminal Four, new airline on the block Vietnam Airlines are battling baggage woes in the lead up to the holiday period. Rookie engineer Mo comes up with an ingenious solution to ensure no-one is stranded abroad without their luggage.

There's something smelly in Cargo that Border Force have to get to the bottom of. Passenger Experience Manager Harry rushes to a gate that's had its door smashed in and King of Terminal 2 Demi has 700 passengers descend on him - one being a pop star.

Britain is on the cusp of holiday season and Heathrow is revving up for passengers from all over the globe. We meet a new member of the Passenger Experience Manager Team: Suki.

Flying into Heathrow are an endangered parrot and a polar vortex. Whilst Officers Dave and Terry hunt for a wanted man gone missing on a plane, airside Ian and slicker-for-the-rules Steve battle snow in a blizzard to keep the runways open.