Dyke Davidoff Masson Syndrome (DDMS) is a rare condition with varied presentation. Characteristic features are cerebral hemiatrophy, enlargement of ipsilateral ventricle, enlargement of ipsilateral air sinuses and clinical finding of contralateral hemiparesis or hemiplegia and seizures. DDMS may have comorbid intellectual disability or speech disorder but presentation with psychiatric disorders is rare. We present a case of DDMS who first came to attention with behavioral problems associated with aggression, social disinhibition and with alcohol and cannabis use disorder.