Anaplastic thyroid carcinoma accounts for 3%–4% of thyroid malignancies worldwide and is aggressive in nature with a median survival of 6 months at diagnosis. A 67-year-old lady with a hard goitre presented with compressive symptoms and mild hypothyroidism. Ultrasound scan revealed a Thyroid Imaging Reporting and Data System 5 lesion with suspicious left-sided cervical lymphadenopathy. Anaplastic carcinoma was diagnosed by fine needle aspiration cytology. Left-sided thyroid tumour with possible carotid sheath infiltration and left-sided cervical lymphadenopathy was seen on contrast-enhanced computed tomography of the neck. She underwent total thyroidectomy with therapeutic bilateral selective central and lateral cervical lymphadenectomy. Involvement of the aero-digestive tract and carotid sheath was not observed intra-operatively. Histology reported anaplastic carcinoma with deposits of papillary carcinoma in affected lymph nodes. Oncological management was commenced thereafter. Anaplastic thyroid carcinoma usually presents as advanced disease. However, current guidelines suggest a multimodal approach comprising of curative surgery whenever feasible with adjuvant radiotherapy and chemotherapy. For patients with stage IV a/IV b loco-regional disease as in our patient, total thyroidectomy with therapeutic lymphadenectomy to achieve R0/R1 resection plus adjuvant therapy is the current accepted practice. For locally advanced disease, surgery maybe opted after down-staging. The aim is to resect tumour wholly and not merely de-bulking. The presence of papillary carcinoma in lymph nodes points towards anaplasia occurring in a background of differentiated thyroid carcinoma in our patient similar to what literature suggests. This has implications in post-operative thyroxine suppression and radioiodine ablative therapies.