Introduction: Acute respiratory distress syndrome (ARDS) is an uncommon complication of hemophagocytic lymphohistiocytosis (HLH). Non-specific findings that mimic other diseases make timely diagnosis and treatment challenging. We present a rare case of severe ARDS and multiorgan failure from secondary HLH due to peripheral T-cell lymphoma. Case presentation: A middle-aged female presented with dry cough and fever for three days. On presentation, the patient was febrile to 105°F and hypoxic to 88% on room air. Chest X-ray showed bilateral interstitial infiltrates. Laboratory investigations showed lymphopenia and elevated inflammatory markers. The viral panel, including coronavirus disease-2019 (COVID-19), influenza, and respiratory syncytial virus (RSV), was negative. Her respiratory status progressively worsened, requiring invasive mechanical ventilation for ARDS. Despite lung-protective ventilation, prone positioning, and the use of paralytic agents, the patient continued to remain hypoxic, necessitating extracorporeal membrane oxygenation (ECMO) support. The patient was started on antibiotics and high-dose steroid. Thereafter, she developed a leukemoid reaction, and the ferritin level started rising; raising suspicion for lymphophagocytosis. During this time, she also developed acute liver and kidney failure and required multiple vasopressors and renal replacement therapy. Eventually, a diagnosis of mature peripheral T-cell lymphoma was established. Subsequently, her respiratory status and multiorgan failure significantly improved, and ECMO was explanted after 2 weeks. She was started on etoposide and steroid, and eventually discharged after 6 weeks. Discussion: This is the first case describing a successful implementation of ECMO in an adult diagnosed with ARDS secondary to mature peripheral T-cell lymphoma; allowing for recovery of respiratory status, which was compromised during the initial cytokine storm and provided time to establish the diagnosis and initiate appropriate treatment of secondary HLH mature due to peripheral T-cell lymphoma, and in the end, prevented a fatality. We believe that ECMO may be appropriately instituted in rapidly deteriorating patients with an unknown illness refractory to conventional therapy, to allow for end-organ recovery, to reach a diagnosis, and to administer appropriate therapy.