 He made his debut with an uncredited bit in the Dick Foran Western, "The Devil's Saddle Legion" (1937).He had small parts in "That Certain Woman" (1937) with Bette Davis; "Back in Circulation" (1937) with Pat O'Brien; "The Radio Murder Mystery" (1937) with Ronald Reagan; "Alcatraz Island" (1937) with John Litel; "Over the Goal" (1937) with June Travis; "The Adventurous Blonde" (1937) with Glenda Farrell; "Missing Witness" (1937) with Litel; and "The Invisible Menace" (1938) with Boris Karloff.Parker's first notable film role was in "A Slight Case of Murder" (1938) with Edward G. Robinson.