An obese diabetic male presented with self limiting diarrhoea of 1 day duration, which had started after he ate sausages. Examination was unrevealing except for persistent low blood pressure. Computed tomographic (CT) scan, done to rule out retroperitoneal bleed, incidentally showed air in the gall bladder. He underwent emergent cholecystectomy, and a gangrenous gall bladder that grew Clostridium perfringens was removed. Emphysematous cholecystitis is not so infrequent, although only rarely does it present as diarrhoea alone. A high index of clinical suspicion is necessary as even advanced presentation can be subtle and appropriate radio imaging essential. Although abdominal radiograph and ultrasound could be useful, a CT scan is diagnostic. The CT scan and its classical finding confirmed the diagnosis, and it reiterates the importance of timely identification and urgent action, as emphysematous cholecystitis is associated with high mortality.