Although the finding of appendiceal duplication is uncommon, its misdiagnosis and mismanagement may yield poor clinical outcomes and serious medicolegal consequences. Laparoscopic surgical exploration was performed on a 17-year-old male patient with right lower quadrant pain and a history of a previous appendectomy. Inspection of the cecum revealed a second appendix, which was retrocecal, ruptured, and gangrenous. Appendiceal duplication should be considered in all cases of lower abdominal pain, and careful inspection of the cecum for appendiceal anomalies should be performed. The Cave-Wallbridge classification system will be presented to assist surgeons in diagnosing appendiceal duplications.