Watch UK Border Force

A freak snow storm shuts down the British transport system. Just one flight lands at Heathrow, re-directed from Gatwick. A charismatic passenger from Antigua charms the immigration staff. But his complex case creates a division between the immigration officer and her boss.

The owner of a nail bar in Southampton is an asylum seeker whose partner is a known illegal immigrant. He's suspected of employing other illegal immigrants as nail technicians. The enforcement team find the owner's girlfriend holding a baby that hasn't been registered and the employees deny being illegal. The team has its work cut out deciding out who stays and who goes.

At Heathrow's Terminal Two a Nigerian with a forged passport is stopped by immigration. His tales of murder and robbery are undermined by his insistence that he is only 15 years old and has been sent here by his Uncle London. It's a fascinating case with a surprise ending. Also in this episode is the "euro criminal" stopped at Calais.

For the first time television cameras go inside the British High Commission in Lagos, Nigeria. It's a city that has a worldwide reputation for fraud and where travel documents are sold openly on street corners. Here the UKBA visa team are swamped with applications for UK visas, and they rarely have a dull day.

We have rare access behind the scenes in an Immigration Removal Centre where the UKBA officers are planning a mass deportation on a specially chartered flight, codenamed Operation Aardvark. In London the enforcement team bust a network of illegal workers at the home of a Chinese takeaway owner. In a room with 6 beds they find a group of men about to eat their dinner.

At the British High Commission in Lagos a pig farmer is quizzed about his colourful history in Britain of dodgy travel documents and a fracas with the police. He accuses the British visa system of letting him down and preventing him from running his pig farm. Visa clearance officer Phil Morgan tries to find his way through the bluster.

A couple from Guyana are thought to have been living under stolen identities for over 13 years. UKBA's Criminal Investigation Team have been investigating this for a year and we join them on the day they make a surprise visit to the couple's home. This leads to confessions of guilt and relief as they reveal they got away with it for so long.

A Jamaican man is arrested in Birmingham on his wedding day. He's an overstayer who mistook his certificate to get married as permission to live in the UK. He was sent back to Jamaica. In Glasgow a Pakistani national is arrested at the registry office minutes before he was to be married to a Scottish woman. The man claims it's true love. The bride says she was paid to be there.

A piece of scrub land in Calais has been nicknamed the jungle. It's where "clandestines" lie in wait to sneak on to trucks heading for Britain. We film in the jungle to find out why, after travelling thousands of miles, the immigrants want to get into Britain and not just stay in Europe. We film with the teams whose job it is to search trucks to stop this illegal human traffic.

Britain's biggest visa fraud case is busted by UKBA and the Met Police. Jatinder Sharma a solicitor who has previously represented Abu Hamza, set up a company called Univisa to help foreigners into Britain using fake documents. Sharma earned millions of pounds charging huge fees; he and his two wives were given sentences totaling 21 years.