Stonemason Andrew Knightley is pushed under a London Underground train during the morning rush hour. DI Max Arnold and his partner, DS Priya Shamsie, together build a picture of a lonely, devout, and troubled man who believed a spirit was leaving him vengeful Biblical messages. But the killer is flesh and blood, and a more earthly explanation may be found in the truth of Knightley's life.

A popular security guard is stabbed to death on a patch of waste ground. He leaves behind his terminally ill wife and at first, it appears he died as a result of a drug deal gone wrong. However, as Max and Priya soon realize, nothing is as it seems.

A woman at a luxury retirement home dies mysteriously, and with no signs of forced entry, suspicion falls on the staff and residents; tensions within her family point to another cause, harking back to their time in Apartheid-era South Africa.

Jack Felton, the owner of a fruit and vegetable delivery company, is found stabbed at home in what looks like a frenzied attack; the detectives must unravel romantic jealousies, family conflicts and business rivalries to nab the killer.