Introduction: A Dieulafoy's lesion is a large tortuous arteriole that can cause life-threatening hemorrhagic shock, occurring in 1-2% of cases of upper gastrointestinal bleeding. It is an underdiagnosed cause of obscure massive hematemesis because its small size and location makes it difficult to visualize. Case Description/Methods: An 84-year-old white male with atrial fibrillation, on apixaban, presented for large-volume hematemesis. Physical examination revealed blood pressure of 80/60 mmHg, pulse of 110 beats/minute, orthostasis, temperature of 36.9°C, and an ill-appearing individual with a diffusely tender abdomen. Laboratory examination revealed leukocytes of 19.9 bil/L (normal: 3.5-10.1 bil/L), hemoglobin of 11.2 g/dL (normal: 13.5-17 g/dL) which dropped to 7.5 g/dL in 2 hours. Computed tomography of the abdomen and pelvis without contrast demonstrated diffusely distended stomach with internal debris concerning for blood products. He was intubated for airway protection and transfused 1-unit of packed-erythrocytes. Intravenous pantoprazole and norepinephrine were administered, and he was transferred to the medical intensive care unit. He was also incidentally found to have coronavirus disease (COVID-19). With precautions taken for COVID-19 infection, he underwent emergent esophogastroduodenoscopy revealing a bleeding vessel, Dieulafoy's lesion, proximal to the gastroesophageal (GE) junction (Figure 1) with a huge amount of clotted blood at the gastric fundus and body. The vessel was injected with 3 mL of epinephrine and two clips were placed achieving hemostasis. The next day, the patient's blood pressures improved, his hemoglobin stabilized to 9.2 g/dL and he was extubated. Discussion: A Dieulafoy's lesion is commonly located in the stomach, with majority found proximal to the GE junction however it can be hidden in the gastric mucosal folds. Treatment includes heat probe coagulation, epinephrine injection or banding. Our case demonstrates that rare diagnoses such as a Dieulafoy's lesion should be considered in the differential diagnosis in patients presenting with hematemesis as timely endoscopic treatment can often result in immediate cessation of bleeding. When the bleeding vessel cannot be located, these patients are often referred for angiography.