Ralph Harrison gives his wife Penelope his late mother's diamond necklace as a wedding anniversary present and persuades .her to wear it to the fund raising disco at the Ashfordly Grammar School. During their absence their house is broken into, but only a set of teaspoons is taken. Sergeant Merton suspects that the thief was looking for something specific. He may be right because the following day the house is broken into again and the diamond necklace is taken. Gina is afraid of spiders. Vernon Scripps thinks that hypnosis may cure her and offers his services because he is an (instant) expert on hypnosis. When he is learning how to he accidentally hypnotizes David without noticing. Sergeant Merton continues to have dizzy spells and Dr. Summerbee finds out that he is diabetic. This may be bad for the good sergeant, but it most certainly causes warm feelings to develop between him and Dr. Summerbee's secretary Jenny.