Plot hole: At the end of the previous episode Foyle infiltrated the Fisher household and cut the telephone line. However in this episode, taking place just the morning after, no mention at all of the event is made and Bert and Cec off camera phone the police with no anomalies reported.
Plot hole: The coroner finds the stones "in the nasal cavity" after Miss Fisher's intuition, but he already had examined it in both cases due to the bleeding. Also, it's inexplicable how with the previous case being ruled as the death of a drug addict with no particular findings, the coroner would have still lying around the body to examine for autopsy even when Hugh said the body was found a week before.
Answer: Louisa's watch was broken during the struggle to get away from her attacker.
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