A case of multiple sclerosis is described in which spasmodic torticollis occurred abruptly and abated after 1 year. Magnetic resonance imaging (MRI) demonstrated a lesion in the mesencephalon. Other symptoms and physical signs that developed at the same time as the spasmodic torticollis were compatible with the lesion that had not been present on MRI 18 months previously. There are very few reports of spasmodic torticollis due to an identified focal lesion; there is evidence from experimental work on animals that midbrain lesions may cause spasmodic torticollis but there has been no previous human example.