Neck pain is a common presentation in emergency departments that requires the exclusion of serious underlying pathological entities. Acute calcific retropharyngeal tendinitis is a rare and underrecognized cause of atraumatic neck pain and stiffness. Although this entity has been reported previously, it is often poorly recognized and is often confused with other more serious lesions, such as infectious, traumatic, and neoplastic conditions. Clinically, it can be very difficult to distinguish from these three disorders, and a definitive diagnosis can only be established using imaging studies. A knowledge of the characteristic clinical spectrum and, most importantly, its imaging features is crucial for making the correct diagnosis of this uncommon cause of neck pain. The authors present their experience with one case to highlight the characteristic findings of this disorder on plain radiography, computed tomography, and magnetic resonance imaging.