A 56-year-old woman with no medical history was admitted with acute onset hemiballistic-choreiform movements of right extremity. On admission, her serum glucose and osmolality were elevated. Her glycosylated haemoblobin (HbA1c) was 17.9 with average blood sugars of 467 mg/dL. A CT scan of the brain revealed unilateral hyperintensities in the basal ganglia. A complete stroke work-up, including MRI and MR angiography of brain was otherwise unrevealing. Subcutaneous insulin was instituted, which led to complete resolution of her symptoms within 48 h of hospital admission. She was readmitted 4 weeks after her initial discharge for similar, but less severe, symptoms. This time her HbA1c was 13.9 with an average blood sugar of 352 mg/dL. A repeat MRI demonstrated a persistent abnormal signal within the left basal ganglia without infarct. She was started on subcutaneous insulin. Her symptoms improved but did not resolve. Haloperidol and gabapentin were initiated and she was again discharged after stabilisation to a rehabilitation centre as per physiotherapy recommendations.