A 46-year-old man with a history of asthma and psoriatic arthritis on adalimumab presented with fever, tachycardia, and hypoxia. He was diagnosed with pleural effusion and started on antibiotics, as it was noted to be an exudative effusion. Patient failed to improve on multiple courses of antibiotics, and his blood and pleural fluid cultures were negative. He was then started on prednisone 1 mg/kg and showed remarkable recovery. He was diagnosed with adalimumab-induced serositis.