Joseph Losey's The Servant hasn't lost any of its mystery over the years since 1963; it might even have gained a bit.
Tony (James Fox), a British aristocrat, hires the mysterious Hugo Barrett (Dirk Bogarde) as his household servant. The new employee soon begins to cause unrest in the household, and Tony is forced to send him away. But Barrett's influence extends further than Tony realizes, and he finds himself entangled in an intense psychological war with his former valet. Servant and master square off in a battle that redefines each man's understanding of fear, desire and class. The Servant summons up all one's irrational fears and its baroquely sinister atmosphere invests the most ordinary event with middle-of-the-night creepiness. Losey does masterly work in confined spaces while Bogarde is brilliant as usual.
UK 1963 Joseph Losey