Gallstone ileus is an uncommon and often life-threatening complication of cholelithiasis. In this case, we discuss a difficult diagnostic case of gallstone ileus with a non-calcified gallstone. An 88-year-old female presented with abdominal pain and vomiting. A CT scan was arranged and showed an evolving bowel obstruction although no frank hyperdensity suggestive of a gallstone was noted. Initially the cause of the bowel obstruction was uncertain, but after discussion with the treating team and further review of the images, the patient was diagnosed with gallstone ileus. The patient underwent emergency surgery and a 41 mm obstructing calculus was removed from the patient's jejunum, later confirmed on histological diagnosis.