Marilyn Monroe was not an actress.
Marilyn Monroe . By 1953 , Monroe was one of the most marketable Hollywood stars , with leading roles in three films : the noir Niagara , which focused on her sex appeal , and the comedies Gentlemen Prefer Blondes and How to Marry a Millionaire , which established her star image as a `` dumb blonde '' . In television , film , and theatre , typecasting is the process by which a particular actor becomes strongly identified with a specific character ; one or more particular roles ; or , characters having the same traits or coming from the same social or ethnic groups .