Pneumatosis intestinalis (PI) is a condition characterised by gas-filled cystic malformations on the intestinal wall. It is often secondary to an underlying disease process. We describe the case of a 76-year-old gentleman who presented with intermittent abdominal pain, altered bowel habits and weight loss. Barium enema was unremarkable, apart from sigmoid diverticulosis. CT scan found evidence of pneumatosis on small bowel walls with benign pneumoperitoneum. As there was no sign of intra-abdominal crisis, he was initially treated conservatively. Unfortunately, he required re-admission 6 weeks later with symptoms of bowel obstruction and clinical signs of perotinitis. At laparotomy, he was found to have extensive small bowel infarction due to volvulus from 'twisting' around the axis of superior mesenteric vessels. Evidently, this occurred secondary to a congenitally long small bowel mesentery that predisposed him to volvulus. Extensive small bowel resection was performed. The postoperative course was complicated by persistent hypotension, which proved fatal. This case report draws attention to the rare association between PI and small bowel volvulus predisposed by a congenitally long mesentery, which can present initially with a benign picture (intermittent, reversible volvulus), but subsequently be complicated by lethal bowel infarction (irreversible volvulus). This case raises several issues about the management of this rare condition. Clinicians must realise that PI, though often benign, can present with lethal complications, and early recognition of such complications can be life-saving.