Objective: To report a rare case of a 28 cm left adnexal torsion requiring surgical intervention including detorsion and salpingectomy Methods: Case report. Results: An 18-year-old nulliparous female with morbid obesity presented to the emergency department complaining of one week of sharp right lower quadrant pain with nausea and vomiting that had acutely worsened. Vital signs were notable for tachycardia, but otherwise within normal ranges. She had a significant leukocytosis. Her pregnancy test was negative. A CT abdomen/pelvis was obtained that demonstrated a large multiloculated complex cystic mass measuring 28.5 x 19.8 x 13.3 cm with possible origin from the ovaries that could represent a serous cystadenoma. Additionally, the scan was remarkable for a heterogeneous and enlarged left ovary measuring 7.6 x 5.9 x 7.2 cm, surrounded by free fluid and mesenteric edema. On examination, she did not demonstrate any surgical abdomen findings. Her pain improved with pain medication. She was admitted, tumor markers obtained, and an ultrasound ordered. The ultrasound demonstrated normal appearing right ovary with present doppler flow and a simple cyst measuring 6.6 x 5.1 x 6.1 cm. The left adnexa was noted to have a complex versus solid mass with unclear boundaries of the ovary. Also noted on the ultrasound were two large simple midline cysts measuring 10.5 x 9.1 x 11.8 cm inferiorly and 18.2 x 15.5 x 17.2 cm superiorly. No free fluid was seen within the right upper quadrant on ultrasound. The view of the left upper quadrant was suboptimal. Due to these findings, Gynecologic Oncology service was also consulted and after discussion, decision made to proceed urgently to diagnostic laparoscopy with robotic assisted cystectomy versus oophorectomy. Upon laparoscopic entry into the abdomen, a large necrotic-appearing left adnexal mass was visualized coming from the left fallopian tube. Both the left fallopian tube and left ovary were necrotic, with the left ovary being torsed numerous times. After resection of the large left fallopian tube and cyst, the left ovary was detorsed, and the decision was made to leave the ovary in situ. It still appeared necrotic, but its blood supply was intact. There was a large simple paratubal cyst on the right fallopian tube that was also drained and excised. Postoperatively, her right lower quadrant pain resolved, and she was discharged on post-operative day 1. She prescribed a two-week course of doxycycline and metronidazole as pelvic inflammatory disease could not be ruled out. At outpatient follow-up, she was asymptomatic and ready to begin working again. Her pathology report confirmed a large left paratubal cyst with associated findings of ischemia due to torsion and a large right paratubal cyst. Conclusions: Adnexal torsion is a rare gynecologic disorder caused by the partial or complete rotation of the ovary and/or the fallopian tube on its vascular support, which can negatively impact fertility. Prompt diagnosis is key, but definitive diagnosis is only by direct visualization. The differential diagnosis for acute onset of severe pelvic pain with nausea and vomiting is broad and includes ectopic pregnancy, pelvic inflammatory disease, endometriosis, ruptured ovarian cyst, urologic issues and gastrointestinal issues. Commonly, ultrasound is used to help evaluate a possible torsion with several classic findings that were not noted in this case, other than a mass. The two best known risk factors for adnexal torsion are a mobile ovarian mass and a history of prior torsion. Although large ovarian masses greater than 5 cm are more likely to cause torsion, some experts hypothesize that very large masses are less likely to torse given the constraints of the pelvis. However, such was not the case here. Additionally, it has been observed that adnexal torsion typically affects the right adnexa due to theoretical protection from the descending colon on the left. Given that the case presented did not have any of the typical imaging findings for adnexal torsion and that her pain was on the right but the torsion on the left, it is important to maintain a high level of suspicion when evaluating patients with acute onset pelvic pain of any location with nausea and vomiting.