We present the case of an elderly non-diabetic female who was admitted to hospital as an emergency due to loss of consciousness. Her clinical presentation was consistent with hypoglycaemia due to a massive insulin overdose. However, the patient refuted the possibility of insulin administration, and the circumstances were reported to the police for investigation. This case demonstrates the clinical and biochemical characteristics of insulin overdose. Furthermore, it serves to illustrate the sequence of events that may be created when foul play is suspected, and the factors related to patient confidentiality that require consideration by the responsible physician.