The supporting character was invaluable to the massively popular sitcom, but it turns out, Christopher almost didn’t make it onto the series. Initially, the show cast an actor named George Morgan to play the priest role, but he only appeared in the pilot episode. He was replaced with Christopher beginning with episode two, but according to an interview later-season showrunner Burt Metcalfe did with The Hollywood Reporter in 2018, the actor totally blew his initial audition. “We made the pilot with a different Father Mulcahy,” Metcalfe recalled. “He was the only performer [series creator Larry Gelbart] wanted to change.”
“Bill was my great white hope,” Metcalfe shared. “He blew the audition, though. Larry wrote in a specific rhythm and if you don’t adhere to it, you destroy the humor.” Apparently, though, Christopher still possessed something that Gelbart wanted for the character, who would be playing a relative straight man in contrast to the wilder, hedonistic members of the 4077th.