|This article does not cite any references or sources. (December 2009)|
He was with Lux Radio Theater as a utility supporting player in nearly every broadcast from 1937-1939 (notably as Sleepy in Snow White and the Seven Dwarfs), also serving as an assistant director handling the crowd scenes during that time; he continued to work the show sporadically until 1953. Other radio shows in the '30s included roles in the children's Christmas series The Cinnamon Bear (as Santa Claus), the crime drama Big Town (as various gangsters and a stand-in for Edward G. Robinson as Steve Wilson), the soap opera Those We Love (as con man Ed Neely), and The Mickey Mouse Theater of the Air. He later worked for Arch Oboler on Arch Oboler's Plays and Lights Out.
In 1941, he starred as the Nemo-like Captain Craig McKenzie in the now mostly lost sci-fi series Latitude Zero and 12 years later, would star on the true crime anthology drama series Crime Classics. Merrill played Thomas Hyland the host/narrator with a fascination in crime, playing the role deadpan but with subtle humor. Radio comedy appearances included Point Sublime (a regular as jeweler Aaron Saul) and Abbott and Costello (guesting as Santa Claus) and the Life of Riley as Punchy (a punch drunk ex-prize fighter). He also appeared on Escape, The Man Called X, Suspense, NBC University Theater, On Stage, The CBS Radio Workshop, Rogue's Gallery, and The Six Shooter.
In his later years, Merrill continued doing voice-over work, regularly doing film trailer narration work for American International Pictures. Merrill narrated trailers for films such as It Conquered the World, I Was a Teenage Werewolf, War of the Colossal Beast, Teenage Cave Man, Night of the Blood Beast, A Bucket of Blood, Horrors of the Black Museum, The Angry Red Planet, Master of the World, and Burn, Witch, Burn.