We describe the case of a patient with nocturnal frontal lobe epilepsy, presenting with periodic leg movements during sleep and complaining of excessive daytime sleepiness. With the support of intracerebral electroencephalogram recordings and the corroboration of the postoperative outcome, periodic leg movements during sleep and excessive daytime sleepiness appeared to be associated to enhanced arousal instability induced by by recurrent epileptic discharges not detectable on scalp electroencephalogram.