A short murder mystery.
Retired widows Connie and Sable Butterworth have set up a private investigating business. Their third case involves a mysterious night-time visitor.
Jocelyn Kent contacts Connie and Sable and asks them to look into strange occurrences which happen nightly in her office. Every morning, when Jocelyn returns to her office, she discovers items have been moved despite the office being secure.
Not happy with scaring Jocelyn, the intruder has now started to make attempts on Jocelyn's life by sabotaging the drinking water and furniture.
Connie and Sable are soon on the case and set up a night-time vigil. But there is something about Jocelyn's office that bothers Connie. As the case proceeds, she remembers what it is, and the case takes a surprising turn.