Peritonitis secondary to spontaneous rupture/perforation of the gall bladder is a rare condition overall and is even less common in the forensic population. We report the case of a middle-aged man who died from generalized peritonitis from gall bladder perforation due to acute acalculous cholecystitis. This condition usually occurs in critical patients with systemic illness, and although the exact pathogenesis remains unclear, the development of acalculous cholecystitis appears to be multifactorial. Antemortem diagnosis is reliant upon clinical presentation, laboratory data, and radiologic studies. Surgery and appropriate antibiotics are mainstays of treatment; however, there is an emerging role for minimally invasive procedures. Histopathologic features show significant overlap with the calculous type. Although increasing numbers of acalculous cholecystitis have been diagnosed in the critically ill, the fatal presentation of a perforated gall bladder following an undiagnosed case of acute acalculous cholecystitis is unusual in a nonhospitalized and ambulatory man.