(written from a Production point of view)
Curtis also has unconfirmed work on Star Trek as the voice of Jon Daily in "The Conscience of the King" and the Starbase Operations voice in "The Menagerie, Part I". Call sheets show him as doing voice-over work in "The Cage", but this may not have survived the editing process.
Curtis has appeared on a few other television series, including The Man from U.N.C.L.E., Voyage to the Bottom of the Sea, and Mission: Impossible. He also appeared in the 1965 films The Sandpiper and A Patch of Blue.