Desmoid tumours are benign tumours originating from the musculo- aponeurotic structures of the body. They are mainly composed of collagen. These tumours commonly occur in post-partum women in whom they originate from the rectus abominus and in old surgical incisions. Here we present a case report of a young gentleman who presented with an acute surgical abdomen and subsequently underwent a laparotomy and was found to have an inflammatory mass. Histological analysis of this mass revealed mesenteric fibromatosis (desmoid tumour). I wish to present this interesting case because the patient was neither female nor someone who had previously undergone any surgery. It is rare for mesenteric fibromatosis to present with intestinal perforation and only one case been reported in the literature thus far (1). An important learning point from this case is that rare pathology can manifest itself with common signs and symptoms.