Dramatisation of the real-life case of George Joseph Smith who was hanged in 1915 for the murder of his three wives, each of whom he killed in turn by drowning them in the bath while trying to make the deaths look like accidents.

The peacefulness of the Midsomer community is shattered by violent crimes, suspects are placed under suspicion, and it is up to a veteran DCI and his young sergeant to calmly and diligently eliminate the innocent and ruthlessly pursue the guilty.