Simple Summary: Ovarian cancer (OC), the most lethal gynecological malignancy, usually presents in advanced stages. Unlike other gynecological malignancies, advanced epithelial OC often spreads through peritoneal and lymphatic dissemination to the upper abdomen. Hence, OC necessitates complex surgical procedures usually involving the upper abdomen with the aim of achieving optimal cytoreduction without visible macroscopic disease. Omitting dissection of these particular areas can compromise complete cytoreduction. Neglected anatomical areas that may harbor tumor residues include the omental bursa; Morison's pouch; the base of the round ligament of the liver and hepatic bridge; the splenic hilum; and suprarenal, retrocrural, cardiophrenic and inguinal lymph nodes. These areas are commonly involved and should be rigorously evaluated in every patient with advanced epithelial OC as they often preclude optimal cytoreduction. This article provides a meticulous anatomical description of neglected anatomical sites concealing possible residual disease during OC surgery and describes surgical steps essential for the dissection of these "neglected" areas. Ovarian cancer (OC), the most lethal gynecological malignancy, usually presents in advanced stages. Characterized by peritoneal and lymphatic dissemination, OC necessitates a complex surgical approach usually involving the upper abdomen with the aim of achieving optimal cytoreduction without visible macroscopic disease (R0). Failures in optimal cytoreduction, essential for prognosis, often stem from overlooking anatomical neglected sites that harbor residual tumor. Concealed OC metastases may be found in anatomical locations such as the omental bursa; Morison's pouch; the base of the round ligament and hepatic bridge; the splenic hilum; and suprarenal, retrocrural, cardiophrenic and inguinal lymph nodes. Hence, mastery of anatomy is crucial, given the necessity for maneuvers like liver mobilization, diaphragmatic peritonectomy and splenectomy, as well as dissection of suprarenal, celiac, and cardiophrenic lymph nodes in most cases. This article provides a meticulous anatomical description of neglected anatomical areas during OC surgery and describes surgical steps essential for the dissection of these "neglected" areas. This knowledge should equip clinicians with the tools needed for safe and complete cytoreduction in OC patients. [ABSTRACT FROM AUTHOR]