The Shadow at the Door

When Paul Conister heads upstairs he doesn't return. His wife Maggie goes up to find all the windows are locked from the inside and Paul's phone and wallet are next to their bed.
He hasn't left. And there's no sign of him anywhere.
This case brings missing persons investigator David Raker into contact with three other mysteries.
A deadly discovery by night patrolmen in an Underground station. A cold case with a witness that no longer exists. A tragic shooting of a young man with a terrible secret.
Four stories. One connection. Only Raker can uncover the truth.