1. An affluent elderly lady dies. The death certificate cites 'natural causes', but the servants are uncomfortable.

A parlourmaid decides to go to New Scotland Yard, and talk to someone there. She is fortunate, because Detective Sergeant Haig happens to pass through the foyer while she is trying to explain. The busy desk officer intercepts him, and asks to him to listen to the maid's story.

Haig listens politely, but is ready to dismiss the story as tittle-tattle, when he hears one thing which makes him take notice. He goes to report to his boss, DCI Bryce, who also finds the point of interest, and goes downstairs to speak to the maid himself.

The full might of the Metropolitan Police is then focussed on the matter - and a post mortem examination reveals that the lady was indeed poisoned.

Where did the poison come from? How was it administered? Who did it, and why? In the leafy South London suburb of Dulwich Village, Bryce and Haig investigate the happenings, and sort out who is innocent, and who is guilty.

2. DCI Bryce is sent to Norfolk, where two solicitors have been killed at different times. There are obvious connections between the crimes. First, both men were partners in the same law firm. But also, both bodies were found beside local railway lines.

However, shortly before these two men were found, a third body was discovered. This victim didn't seem to have any connection to the firm of solicitors - but he too was found beside a railway track.

A temporary absence of CID officers in King's Lynn causes the Chief Constable to ask Scotland Yard to take the case. DCI Bryce and two of his officers travel to West Norfolk, where they find a local Detective Constable eager to help.

Which of the three victims was the real target, and which murders were either dry runs or red herrings?