This case is of a 39-year-old Filipino woman who within 2 months developed, Cushing's features she had no known comorbidities and no history of steroid intake. The patient also presented with hyperpigmentation of knuckles and toes, metabolic alkalosis and persistent hypokalaemia noted as proximal muscle weakness. The patient was referred to our institution for acutely worsening behavioural and psychiatric changes. Work-up for endogenous Cushing's syndrome revealed a significant adrenocorticotropic hormone production from an ectopic source. Further imaging was requested to locate the tumour, but the patient eventually succumbed to the drastic complications of hypercortisolism. On autopsy, the patient was found to have an ectopic well-differentiated neuroendocrine tumour located at the pancreatic head with metastasis to the right hepatic lobe.