The Servant (Losey, 1963)
If you enter the terms "servant," "losey," and "creepy" into the Google search engine, you get approximately nine hundred hits. Not all of them, of course, are using the "c" word in connection to Joseph Losey's 1963 film starring Dirk Bogarde and "introducing" James Fox, but enough of them are to make it clear that "creepy" is the adjective of choice for talking vaguely about Losey's film without having to get too specific.