All ten episodes from the third series of the BBC television drama, following the missions of a team of dedicated MI5 agents. In 'Project Friendly Fire', Tom (Matthew MacFadyen) has gone missing after shooting his boss, and Zoe (Keeley Hawes) has to prove Tom's innocence. In 'The Sleeper', Harry (Peter Firth) reactivates a sleeper agent to infiltrate a terrorist cell. In 'Who Guards the Guards?', the team are called in to investigate an assassination attempt on a famous novelist. In 'A Prayer For My Daughter', Middle East peace talks collapse after the assassination of a delegate, and the team investigate a pro-Israeli newspaper baron. In 'Love and Death', a day-off finds the team killing time in their own wildly different ways. In 'Persephone', an undercover policeman is killed in an operation, and Zoe finds herself charged with manslaughter. In 'Outsiders', a computer hacker is tracked down to a mosque, but two agents go missing when they investigate. 'Celebrity' sees the team investigating the kidnapping of a celebrity couple's new baby. In 'Frequently Asked Questions', after a known mercenary is seen at an ex-Soviet arms fair, a missile goes missing and MI5 suspect that it is going to be used in a terrorist strike on London. Carter (Rupert Penry-Jones) is faced with an ethical dilemma, as he considers the use of torture to get the information he needs. Finally, in 'The Suffering of Strangers', Carter is forced into an impossible choice after kidnappers capture Danny (David Oyelowo) and Carter's family.