Sweet Tooth by Ian McEwan

Is this a romantic spy novel or a romance with a dash of espionage? Serena is drawn into MI5 by a sophisticated older Cambridge connection. It is 1972.  The "soft Cold War" is being fought on literary as well as philosophical fronts, the IRA is a disrupting issue, and England's labor issues are creating a sense of gloom and doom.  Serena falls in love - more than once.  Each affair complicates her position in MI5.  Some complications she knows and others she and the reader may not understand until he very end.  Besides all that, this often reads like a discourse for "writing and literature 101". It almost requires reading with a British accent.