Successful endodontic treatment is based on the holy trinity of access preparation, chemo-mechanical cleaning and shaping and three-dimensional obturation of the root canal system. The complexity of root canal system and its variations may adversely affectthe endodontic treatment outcome. Therefore it is necessary to be aware of the possible anatomic variations for their successful management. Adental practitioner seldom faces C-shaped canal configuration in the mandibular second molar during its endodontic treatment. This type of canal configuration may cause diagnostic and anatomic difficulties which can lead to endodontic mishaps, if not managed strategically. The presented case series unveils the endodontic management of the different types of Cshaped canal configurations that would occur in mandibular second molars through a case series of 5 reports.