Karla's choice : a John le Carré novel

A novel set in the world of John le Carré's iconic spy, George Smiley. It is spring in 1963 a Russian agent has defected in the most unusual of circumstances, and the man he was sent to kill in London is nowhere to be found. Smiley reluctantly agrees to one last simple task: interview Szusanna, a Hungarian émigré and employee of the missing man, and sniff out a lead.