A subset of patients with major cerebral hemispheric ischemia due to distal internal carotid artery or proximal middle cerebral artery occlusion has rapid spontaneous improvement of neurologic deficits. This phenomenon has been designated the "spectacular shrinking deficit." A 79-year-old woman had the sudden onset of neurologic deficits consistent with a large right middle cerebral artery territory infarct. Serial multimodality imaging studies documented distal propagation and fragmentation of a proximal middle cerebral artery thrombus coinciding with rapid clinical improvement. Spectacular shrinking deficit provides a unique insight into the underlying characteristics of a patient population not treated with thrombolytics with impressive recovery from major hemispheric ischemia.