Fire on the Hill by Frank Rockland

What really happened on the night of February 3, 1916, when a fire destroyed the centre block of the Canadian Parliament buildings? Inspector Andrew MacNutt of the Dominion Police’s Secret Service, his wife Katherine, and Count Jaggi know, since they were there in the reading room when the fire started. Ever since the war began MacNutt has been struggling to secure Canada’s borders against acts of sabotage organized by German military attachés based in New York City. The good news is that the Americans have finally ordered them back to Germany. The bad news is that Berlin has sent one of their best operatives, Count Jaggi, to replace them. Using his cover as a Belgian Relief representative, Count Jaggi visits Ottawa, where he meets and is attracted to Katherine, who is helping him organize a local fundraiser. Unaware that Inspector MacNutt has intercepted his secret messages and is hot on his trail, Count Jaggi takes a final trip to Ottawa to see Katherine, with tragic consequences.