Our patient was a 30-year-old woman with a history of schizophrenia and major depressive disorder who presented with worsening depression symptoms and a profoundly higher water intake over the previous 48 hours. She was found down by family at home, agonally breathing, was subsequently intubated and transferred to our facility. She arrived with absent brainstem reflexes, not breathing independently of the ventilator, hypothermic, hypotensive, bradycardic, and without motor responses. The patient was initially hyponatremic to 116mEq/L with a measured and calculated serum osmolality of 251 and 245 mOsm/k respectively, with undetectable urine sodium. CT head displayed diffuse cerebral edema, absent cisterns, and significant brain herniation. Overall, concerning for brain death secondary to hypernatremia and cerebral edema. She was started on mannitol and targeted temperature management was maintained for 24 hours post arrival after correction of underlying metabolic derangements. Drug screen was negative, and toxicology was consulted without discovery of any coinciding agent. An EEG and nuclear medicine blood flow study was completed prior to brain death examination which confirmed the presumed initial presentation.