Presented here is a case where 8 canals were located in a mandibular first molar. A patient with continuing pain in mandibular left first molar even after completion of root canal treatment was referred by a dentist. Following basic laws of the pulp chamber floor anatomy and under magnification, 8 canals were located with 3 in mesial root and 5 canals in distal root. At 1 month follow-up patient was asymptomatic .The story emphasizes how understanding the rules of pulp chamber anatomy and following them when looking for extra canals might help to avoid missing canals. The case emphasizes how understanding the rules of pulp chamber anatomy and following them when looking for extra canals might help to avoid missing canals.