Annie Woodrow is arrested for the murder of her old school friend, Frances Trevelyan. Ten months later, her case comes to court and although Barnaby was the arresting officer, he is still not convinced that the full story has come out. It is likely that the prosecution will suggest that Annie was obsessed with Frances' husband John - that she is a deluded stalker who would stop at nothing, including murder, to obtain the object of her desire. But Annie has always denied having any feelings for John and he too has denied any sort of relationship with her. Barnaby is not so sure.