Following the enforcement teams at Heathrow Terminal 3, Calais, Dover.

A woman arrives at Heathrow from Cape Town claiming she's there for a training course; in reality, she's come to earn money to send back home; officer Kay Lomas is handed the case of a "student" who is trying to re-enter the country from India.

At a reporting center, asylum seekers, foreign criminals and those caught working illegally come to make weekly reports and show they are following instructions while their paperwork and legal status is processed.

A charismatic passenger stirs up conflict between the immigration staff, while customs officers target those smuggling animal products.

A suspected in a smash and grab heist at a jewelry store in Austria; officers play spot the imposter in Lagos, Nigeria.