The authors report on the case of a 15-year-old boy with Crouzon syndrome (CS) who presented with headache and facial diplegia. He had undergone several craniofacial interventions and a posterior fossa decompression for tonsillar herniation caused by the CS. A ventriculoperitoneal (VP) shunt had been inserted for hydrocephalus. Emergency computed tomography (CT) disclosed slight dilation of the ventricular cavities compared with their appearance on a baseline CT scan. Magnetic resonance imaging showed a deformed brainstem but no compression at the occipital foramen; there was no apparent explanation for the facial diplegia. The neuroophthalmological examination revealed neither papilledema nor oculomotor palsy. Electromyography confirmed incomplete peripheral facial diplegia. The patient underwent emergency shunt revision, during which complete obstruction of the ventricular catheter and severe cerebrospinal fluid hypertension were found. After surgery, cranial hypertension symptoms completely resolved and the facial diplegia improved slowly with a persistent and incomplete right superior facial palsy. Cranial 3D CT scanning reconstructions and brain magnetic resonance imaging demonstrated severe petrous bone distortion that could have been responsible for direct stretching injuries on the facial nerves at the level of the internal acoustic meatus. The present case represents the first reported occurrence of VP shunt failure as revealed by a facial palsy; the authors discuss the pathophysiology of facial palsy in intracranial hypertension.