Malignant hyperthermia is a potentially fatal complication of general anesthesia that may occur with greater frequency in some patients with ptosis or strabismus. The history of our knowledge of this recently described condition is outlined. The clinical features, pathophysiology, and differential diagnosis are reviewed in detail. A protocol for the treatment of the acute malignant hyperthermia crisis and guidelines for the management of susceptible patients are suggested. The medicolegal implications of the occurrence of such a crisis are discussed.