Harry is an undercover agent for the British army sent to Northern Ireland to infiltrate the IRA and find (and terminate) the assassin of a British Cabinet Minister. Harry is alone, the army hasn’t been told he is being put in place, his wife is fed up with him and his job, and his one new friend, an Irish woman who falls for him, will be consumed by his relentless search for the assassin.
The British Government cabinet minister Henry Danby is murdered by an IRA gunman, Billy Downes, in front of his wife and children as he’s leaving for work. Downes then escapes to Belfast and army officer Harry Brown is sent undercover into Belfast’s Catholic community to track down the assassin. Brown is chosen for the mission because he is an Ulsterman who had previously done similar work in Oman.