Adam Dalgliesh is sent to nursing school to investigate the death of Heather Pearce, A student poisoned during demonstration. He uncovers the secret that infect the school, Dalgliesh must identify the killer before the strike start again.

After the death of another student nurse at nightingale house, Dalgliesh's hunt for the murder deepens. A patient died at hospital might hold the answer, But Dalgliesh curiosity puts his life in danger.

Dalgliesh travels to Dorset to visit his friend Father Michael, but it turns out the man died two weeks earlier. To make things worse, Dalgliesh learns that another resident of the estate died a suspicious death a few weeks before that.

WIth Grace dead, the future of the estate is more uncertain than ever. Wilfred organizes a vote to establish whether he should continue as the residents' spiritual adviser. Dalgliesh digs deeper into the operation's secrets.

Dalgliesh digs into the Berownes' family secrets. He eventually confronts the killer - and reveals some deeply personal things about himself.