The case of a 60-year-old female with severe and rapidly progressing Cushing's syndrome with fatal consequences is described. Both the clinical and the biochemical findings were consistent with ectopic ACTH production. A computed tomographic (CT) scan revealed intact pituitary and enlarged adrenal glands. Liver metastases were seen but the primary neoplasm was not found. Treatment with aminoglutethimide and other therapeutic measures were unsuccessful. A carcinoma of the right ovary was discovered on autopsy. The tumour cells showed immunoreactivity for neuron-specific enolase (NSE), ACTH and beta-endorphin with differing degree of intensity.