Craniopharyngiomas are reported to be the commonest non-glial tumours of childhood. The classic presentation is typically progressive, commonly manifested as visual field defects, growth abnormalities and/or endocrine disturbance. We report a case of an 11-year-old girl presenting in acute confusional state, with few historical factors suggestive of an intracranial mass lesion and no objective localising signs on examination. Although initially treated as encephalitis, neuroimaging revealed a large craniopharyngioma with acute hydrocephalus and bilateral frontal lobe compression. She was transferred immediately to the local neurosurgical unit and underwent reservoir drainage of the cystic tumour within 24 h. This resulted in immediate symptomatic resolution. This case highlights the importance of early cerebral imaging in the paediatric patient with diagnostic uncertainty and suggests a high index of suspicion for space-occupying lesions in children, despite perceived duration of symptoms.