Mark Allen Shepherd is an actor and artist from Rockville Centre, New York who is best known for his portrayal of the Lurian freighter captain Morn in Star Trek: Deep Space Nine. Throughout the seven year run of Deep Space Nine, Shepherd never received official credit and appeared in other background roles as well. He also portrayed Morn in episodes of Star Trek: The Next Generation and Star Trek: Voyager.

Shepherd received a Bachelor of Science degree in biology from Roger Williams University in Rhode Island which he attended between 1979 and 1984. After graduation, he moved to Southern California and studied at the California Institute of the Arts, focusing on music, film, theater, performance, and interdisciplinary arts between 1986 and 1990.

Shepherd is also an accomplished artist, and he has created numerous abstract impressionist paintings, mixing media types into photo mosaics. In his artwork, he likes exploring abstract concepts as energy, consciousness, perception, and multi-dimensionality. Indeed, twenty-three of his works have been used as set dressing on Star Trek: Deep Space Nine, including paintings in the quarters of Kira Nerys, Julian Bashir, Jadzia Dax, and Jake Sisko.