Even celebrities have to wait in line to enter the UK. Lisa Lea says spotting famous faces is all in a day’s work at Heathrow’s Terminal 3, where she works as an immigration officer.

“They have to queue up with everyone else,” says Lea, who has seen the passport photos of celebrities such as Sir Richard Branson, Chelsea Clinton and David Hasselhoff.

The UK Border Agency is responsible for securing borders and controlling migration. Its officers work to ensure that everyone in the UK is eligible to be here. Lea, who can spend much of her day checking passports and landing cards, says that if someone’s story does not add up the immigration officer takes them aside for further investigations.

“You serve the paperwork to detain them, then the chief immigration officer checks your reasons. We do a baggage search and conduct a full interview.”

The officer can telephone the person’s sponsors, friends and contacts. “Then you have to make a judgment: do they meet the criteria for a visitor and are they likely to go home afterwards? Do they have enough money or someone who is willing to support them?”

The final decision has to be authorised by the chief immigration officer. If entry is refused, the person is sent back on the same day wherever possible. “With some people you know from the minute they arrive that something is up. I have had people say to me afterwards, ‘It was worth a try’. But there are some bitterly disappointed people who have perhaps been students here and built up a life in the UK and overstayed.”

Not all immigration officers are desk-based. Vikki Lacey works for the border agency as an enforcement officer, visiting workplaces and homes to check people’s immigration status.

“No day is ever the same,” she says. One day officers can be visiting restaurants and supermarkets to check work permits, the next day they could be involved in a dawn raid on a house of illegal immigrants. Lacey once found 36 Chinese immigrants living in a two-bedroom house in Peckham, London, which also served as a factory for forged DVDs.

The agency employs 25,000 people in more than 40 countries. Lacey recently spent three months working in Nigeria, making decisions on visa applications. Her ambition is to move into an overseas risk assessment role.

Britain has a duty of care to anyone detained under immigration laws until they are back in their home country. Group 4 Securicor is the main provider of repatriation services for the agency. “The bulk of our recruitment is frontline staff,” says Helen Roffey, its resourcing manager. “We look for interpersonal skills and the ability to deal with a variety of situations, some of which can be quite challenging.”

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