John Sheppard is a fictional character from the science fiction television series Stargate Atlantis. He is portrayed by actor Joe Flanigan and serves as a military officer and pilot in the show. Sheppard is known for his leadership skills and adventurous spirit, often leading missions to explore new worlds and confront various threats. In the series, Sheppard is a key member of the Atlantis expedition, which seeks to uncover the mysteries of the ancient city of Atlantis and protect it from enemies like the Wraith. His character is characterized by a blend of bravery, humor, and a strong sense of duty to his team and the mission.