Here are the posters for every film in the Psycho series, and since I am feeling generous, I will even include those for Gus Van Sant's much maligned, and I would say justifiably so, although I am tempted to give it another chance one of these days, 1998 remake.
Psycho (1960, Alfred Hitchcock)
Psycho II (1983, Richard Franklin)
Psycho III (1986, Anthony Perkins)
Psycho IV: The Beginning (1991, Mick Garris)
Psycho (1998, Gus Van Sant)