We report the case of a young man who presented with a severe acute akinetic-rigid disorder 2 weeks after complete recovery from an episode of pharyngitis. Magnetic resonance imaging scan abnormalities strikingly localized to the basal ganglia were accompanied by serological evidence of recent streptococcal infection and the presence of anti-basal ganglia antibodies in the serum. The case represents an unusually clear example in the spectrum of inflammatory neurological disorders associated with streptococcal infection, an etiology that should be considered in the differential diagnosis of all acute onset movement disorders.