We present the case of a 45-year-old female who presented multiple times to the emergency department with acute low back pain and was subsequently diagnosed with bilateral psoas muscle abscess. Psoas abscess is an uncommon cause of acute low back pain that is associated with high morbidity and mortality. The onset of symptoms is frequently insidious and the clinical presentation vague. Proper diagnosis requires vigilance of the physician to recognize signs in the history and physical examination that are suggestive of a potentially serious spinal condition and initiate further workup. While most patients with acute low back pain have a benign etiology, this case report demonstrates the challenge of diagnosing a patient with bilateral psoas abscess who had few known risk factors and symptoms typical of mechanical low back pain.