Mars was originally considered for the role of Dave Bailey in "The Corbomite Maneuver" , but Anthony Call got the part instead. (These Are the Voyages: TOS Season One) His name was seen on a list of extras for the same episode (as a Crewman), but his character was not seen on screen. He filmed his scenes as Finnegan between Wednesday 19 October 1966 and Wednesday 26 October 1966 on location at Vasquez Rocks and Africa USA. Mars left the acting business in 1969, to become a monk in the Self-Realization Fellowship under the name "Brother Paramananda".