First of six episodes. On the same day that a terrorist attack brings London to a standstill, GP Mona Harcourt receives the devastating news that her brother Kareem has been kidnapped on his way home to the UK from his charity clinic in Lahore. Mona and her family's horror is aggravated by the attentions of the Greater London Police Counter Terrorism Unit and their interest in Kareem's teenage son Danny. Danny has not been seen at university for six weeks, and Mona is determined to find him before the police do.