Peritoneal encapsulation syndrome (PES) is a rare cause of small bowel obstruction (SBO) in patients with no prior history of abdominal surgery. First described by Cleland in 1868, PES is a congenital condition characterised by small bowel encasement in an accessory, but otherwise normal peritoneal membrane. 1 2 A result of abnormal rotation of the midgut during early development, the condition causes fibrous encapsulation of the intestines, thus preventing bowel distention.3 While preoperative diagnosis is difficult, several case reports have described clinical and imaging signs that can help clinicians with not only recognising the condition but also preparing appropriately for perioperative discovery of anatomical variants. 3 4.