Phil Tucker Director, Producer George Nader Roy Actor Claudia Barrett Alice Actor Selena Royle Mother Actor Gregory Moffett Johnny Actor John Mylong The Professor Actor George Barrows Ro-Man the Monster , Great Guidance Actor Wyott Ordung Screenwriter Al Zimbalist Executive Producer Jack Greenhalgh Cinematographer Bruce Schoengarth Film Editing Merrill G. White Film Editing Stanley E. Campbell Makeup Artist Clarence Eurist Production Supervisor Robert Barnes Assistant Director David Commons Special Effects Jack Rabin Special Effects