Tumor lysis syndrome (TLS) is a potentially fatal condition defined both by laboratory and clinical criteria. It is caused by the catabolism of tumor cells which leads to considerable release and elevated levels of phosphate, potassium and uric acid in the bloodstream. These electrolyte derangements predispose patients to renal tubule uric acid precipitation, acute kidney injury, arrhythmias, neuromuscular irritability and even seizures. Although this phenomenon is well described with hematological malignancies, it is also known to occur among solid tumors. We present a rare case of treatment-naïve spontaneous TLS that occurred in a 69-year-old male with metastatic prostate adenocarcinoma with hyperkalemia, hyperuricemia, hyperphosphatemia, hypocalcemia, elevated liver enzymes, AKI and hemodynamic instability. Despite our best resuscitative efforts with intravenous hydration, electrolyte monitoring, Rasburicase and renal replacement therapy, the patient continued to decline, was made comfort care and expired shortly thereafter. Physicians encountering patients with the above presentation must entertain a diagnosis of TLS despite its rarity in solid tumors, as early diagnosis leads to timely treatment, thereby maximizing patients' chances at survival.