Searching for purpose after his wife disappears, Ben MacCarthy works for the Irish Folklore Commission, and goes to profile Kate Begley, the Matchmaker of Kenmare. Then Charles Miller, an American military intelligence officer, arrives, asking for a dangerous favour. Under the cover of their neutrality as Irish citizens, Kate and Ben travel to London and effectively operate as spies, but as they are drawn more deeply and painfully into the conflict, both discover the perils of neutrality - in both love and war.