Anaplastic thyroid carcinoma is a very rare and extremely aggressive carcinoma of the thyroid. Prognosis is dismal and by definition, is classified as stage IV upon diagnosis. Imaging plays a central role in defining the extent of disease, planning therapy, and monitoring the response to treatment. This case report illustrates the aggressive nature of anaplastic thyroid carcinoma and the value of imaging in guiding tumor biopsy, identification of metastases, and planning therapy.