A 74-year-old woman presents with a 7-day history of increasing lower abdominal pains and reduced bowel movements; resulting in absolute constipation.Twenty-four hours prior to admission she also had symptoms of nauseous and significant abdominal distention. Her past medical history included; diverticulitis, type 2 diabetes, hypercholesterolemia, an ultrasound scan in 2005 confirming gallstones, but no previous abdominal surgery.She was initially treated for bowel obstruction and a CT arranged. CT showed a 4.5 cm gallstone in mid-sigmoid colon and a cholecystocolonic fistula. She was booked for colonoscopy±laparotomy, but on the morning of her planned procedure she repeatedly opened her bowels. Subsequent colonoscopy was negative and repeat CT confirmed the stone was no longer within the gastrointestinal tract.