London. December 1981. The IRA is on the attack, a cold war is being waged, another war is just over the horizon, and Stephen Donaldson spends his days listening. When he first joined the Institute, he expected to encounter glamorous, high-risk espionage. Instead he gets the tape-recorded conversations of ancient Communists and ineffectual revolutionaries - until the day he is assigned a new case: the ultra-secret PHOENIX, a suspected internal leak.
Mary-Margaret O'Reilly is seemingly a harmless enough young woman, ready and willing to help out Father Diamond in the Sacred Heart church in Battersea. She may not be very bright, and she is sadly overweight, but she can certainly clean. She is also very good with children, and helps out an Asian woman on her estate whose little boy Shamso is adorable.
What happens to a man who has his ear pressed to the lives of others but not much life of his own? When Stephen Donaldson joins The Institute, he anticipates excitement, romance and new status. This becomes a reality when he is assigned a new case: Phoenix, in which he becomes mesmerized by the voice of the target's wife. Dangerously in love and very lonely, Stephen sets himself up for a vertiginous fall that will forever change his life.
In a church in Battersea, Mary-Margaret O'Reilly sees blood on her hands and believes she has witnessed a miracle. The consequences are both profound and devastating - not just for her but for others, too: Father Diamond, the parish priest, struggling with his own faith. Stella, adrift in her marriage and aching for her ten-year old son, away at boarding school. Alice, counting the days until her soldier son comes home. And Mary-Margaret's mother, imprisoned in a tower block with nothing but her thoughts for company.