Actual causes of death and accurate timing of the death can be essential to a defense in a trial. Dr. Hardy appears as the expert witness for the defense and finds himself opposed by his former professor.

The death of small children is always tragic. The tragedy is increased by unspoken prejudices and the possibility that one of the parents may be to blame.

Murders take place and each crime is similar to the last. One person must have committed them; but who? Another attack. The victim survives but has amnesia and is the only person who can make an identification. A suspect is arrested.

Hardy is trying to piece together the burnt pieces of paper found in the suspect's room. Jo has been asked to try and break the surviving victim's amnesia by hypnosis. The suspect is questioned at length. The case builds up against him.

Martin Ingram, who has been arrested for assaulting Vivien, stands trial for his alleged crime. He is defended by a brilliant woman Q.C. The result of the trial remains in doubt until almost the last moment.

An old man relies upon his daughter to look after him during convalescence but she has her own life to lead.

Threatening suicide is often a cry for help, sometimes that cry is heeded, sometimes assistance is too late.

Hardy is much possessed by the problems surrounding the scientific fact of death. And in this story of an elderly retired Major, his wife and son, the police become totally involved as well.