Spontaneous metastatic clostridial myonecrosis is a rare condition caused by Clostridium septicum. The underlying lesion is usually either a colonic neoplasm or leukemia. The authors reported a 67-year-old female who presented with acute abdomen secondary to a perforated sigmoid cancer and who developed gas gangrene in her right leg. Unfortunately, despite all resuscitative measures, she died. The authors reviewed the literature; the diagnosis of metastatic myonecrosis was based on a high index of suspicion, development of bullae containing gram-positive rods, and subcutaneous crepitus (although this was a late sign). Treatment involves aggressive fluid replacement, high doses of intravenous penicillin, high concentration of oxygen, and surgical debridement, and/or amputation. The mortality remains very high, despite all the above measures