A 12-year-old boy with a history of intermittent right iliac fossa pain presented with an acute severe exacerbation. This was associated with a low grade pyrexia, raised inflammatorymarkers and evidence of localized peritonitis. At open appendicectomy it was discovered that a 6·5 cm appendix containing a large faecolith had torted and become necrotic. This was untwisted to reveal a narrow base but otherwise normal anatomy. Following appendicectomy, the base of the appendix was burried into the caecum, and the patient was discharged two days later. Appendicular torsion is a rare cause of both intermittent pain and indeed acute appendicitis.