Abdominal apoplexy, or idiopathic spontaneous intraperitoneal hemorrhage, is a rare and often fatal condition resulting from a variety of disease processes affecting the arterial and venous abdominal vasculature. Preoperative and intraoperative diagnosis and treatment of abdominal apoplexy are challenging. The source of bleeding may remain elusive even after careful autopsy dissection given the absence of intravascular pressure. Despite these challenges, early diagnosis and rapid treatment remain central to a successful outcome, as nonsurgical mortality has approached 100%. Presented here are two fatal cases of abdominal apoplexy, one involving a patient with arterial dissection of the gastroduodenal artery and one involving rupture of the superior mesenteric-portal venous system with perivascular pseudoaneurysm formation.