Necrotizing fasciitis (NF) is a rare and lethal soft tissue infection that requires urgent surgical intervention. It is most often found in the extremities occurring with precipitating trauma or in immunocompromised states. Signs and symptoms are often vague or missing making early diagnosis very difficult. Our patient presented with flank pain and altered mental status but no known precipitating factors. Computed Tomography showed gas within and around the right paraspinous muscle suspicious for NF. Given NF’s high lethality, early suspicion by emergency physicians of NF in patients with soft tissue infections or with systemic findings of unknown etiology is necessary.