MI5's central computer is being hacked and the number one candidate is school teacher, Gordon Blaney. Show more

When $2 billion is stolen from the last British family-owned bank in London, MI5 is tasked by the government to track down the thief - and the money. Show more

When the President of the United States makes an unscheduled trip to the UK, it's a huge and complex operation. Show more

The French Intelligence Service wants to work with MI5 to catch an arms expert they suspect of trying to sell Eurofighter technology. Show more

Civil service union strikes are bringing the country to a standstill, but MI5 is concerned that a section of the British Army is planning strike action of its own. Show more

Eight Customs and Excise officers are killed on a surveillance operation monitoring the Chala Cartel - Colombia's biggest drug traffickers. Show more

A car bomb kills the Northern Ireland Secretary and his two daughters. Soon after a British army base is attacked. Could this be the start of a revenge campaign by terrorists? Show more

An MI5 agent is identified and tortured inside a Birmingham mosque. Show more

The team take part in an EERIE (Extreme Emergency Response Initiative Exercise). They must act exactly as if there's a national emergency. Show more

In Miami, Florida, a known assassin is asked to come out of retirement for one last task - to kill an Englishman. The only thing is, he has to do it dead. Show more