A method and a circuit arrangement for unlocking a charging plug in an emergency designed for a charging station for charging an electric energy storage of an electric vehicle, having a locking mechanism activated by an electric-motor drive unit. An emergency unlocking controller is a self-sufficient functional block in conjunction with a step-up converter for supplying the electric-motor drive unit with power, the input voltage of the step-up converter stepped up to the nominal voltage of the electric motor. A microcontroller controls and monitors the electric-motor drive unit and the step-up converter and for communicating with a superordinate locking controller generally disposed in the charging station. The step-up converter allows nearly the entire electric energy stored in the storage capacitor connected upstream of the step-up converter to be supplied to the electric-motor drive unit, whereby the motor can be operated at its required nominal voltage.