T he premise of Séamas O’Reilly’s brilliant debut novel is that a Hollywood actor has flown into Derry to star in a new TV series about the Troubles called Dead City, then mysteriously disappeared. But its real interest lies in what happens when a place becomes defined by a particular historical moment, to the extent that stories told about it lapse into formula. As one character says of the TV series: “A young lad coming of age in a time of violence, will he get caught up in everything or find another way through blah blah blah.” O’Reilly is determined to show us that the people of Derry are not so easily stereotyped.…