A rare case of left mesonephric duct malformation consisting of a duplicated ectopic megaureter opening into the ejaculatory duct and ipsilateral upper moiety cystic renal dysplasia is reported to increase awareness among urologists and radiologists of this entity. Magnetic resonance imaging has been shown to be an excellent diagnostic tool for tracking of the trajectory of the ectopic ureter, thereby obviating the need for other invasive diagnostic techniques and permitting surgical correction of the anomaly. The embryology, clinical features, and diagnostic and therapeutic aspects of this rare malformation are presented.