Norman Bates is the main character in
Psycho. As was the case with
Marion Crane,
Hitchcock made several changes to Bates' character in order to make the character more appealing to the
audience.
Robert Bloch characterized Bates as an
overweight,
middle aged alcoholic. When adapting the novel for film, Hitchcock, knowing that it would be hard for the audience to
trust and sympathize with Norman as Bloch had created him, wisely turned him into a
younger,
thinner "boy-next-door".
Hitchcock also introduced Norman after introducing Marion Crane so as to create the impression that the film was about her and not him.
Norman Bates' father died when he was a child, leaving his mother to raise him herself. Mrs. Bates eventually met a man with whom she became involved. He convinced her to buy what eventually became the Bates Motel. Upon his death, Mrs. Bates' physical and mental health began to deteriorate and Norman became responsible for the motel's upkeep.
Motel business eventually slowed after the highway that had originally brought in most of the motel's visitors was moved to another location. Despite a severe lack of business, Norman still changed the sheets and did other motel business that he really didn't have to because people weren't coming.
The first person to patronize the Bates Motel after a reasonably long period of time was Marion Crane. Relieved that someone had finally come to the motel, Norman went out of his way to accomodate her. He made her dinner and even kept her company while she ate it, though he was doing this more to combat his own loneliness than for her benefit. Marion overheard Norman arguing with his mother from the motel while he attempted to prepare her dinner. Mrs. Bates thought that Norman had other intentions for being so kind to Marion.
Norman returned to the motel with Marion's dinner. They discussed the reasons for her 'visit' and Norman's relationship with his mother. In this conversation it is learned that Norman finds taking care of his mother to be burdensome and is troubled by her verbal abuse of him but that he loves her and could not confine her to a mental institution because he believes that they are unfit for humans. Marion decided to go to bed and Norman headed back to the house.
Some time after returning to the house, Norman sees his mother re-enter the house covered in blood. He immediately rushed back to the motel, finding that his mother had murdered Marion while she was taking a shower. In an effort to protect his mother, he cleaned up the bathroom, wrapped Marion's body in a shower curtain, put it in the trunk of her car and buried the car in the nearby swamp.
Norman received another visitor when Milton Arbogast, a private investigator, stopped by the motel in an attempt to locate Marion Crane who had been officially declared as missing. Thanks to Norman's co-operation, Arbogast concluded that Marion had indeed visited the Bates Motel but in order to protect his mother, he said that she had left the morning after she had arrived. Norman mentioned his mother while being questioned and Arbogast asked if he could speak to her. Norman declined, saying that his mother was ill and was not able to have visitors. Arbogast attempted to press the issue but Norman asked him to leave. Arbogast returned to the house but was attacked by Mrs. Bates upon his arrival. Norman discovered the crime and, much like he had with Marion's body, placed Arbogast's body in the trunk of his car and buried it in the swamp.
The worry of Marion's family and friends increased once they failed to hear from Arbogast. They enlisted the help of Sheriff Chambers who contacted Norman. Again attempting to protect his mother, Norman said that Arbogast had indeed questioned him but had left and had not returned. Marion's sister Lila and her boyfriend Sam went to the motel to try to figure things out for themselves.
There are some major spoilers from here on.
While at the motel, Lila and Sam discover
artifacts that prove that Marion was at the motel. Sam distracted Norman while Lila went off to search the house. Once Norman had caught on to what Lila was doing, he ran off towards the house. But he wasn't fast enough to stop Lila from discovering the
decayed corpse of Mrs. Bates in the basement.
Mrs. Bates had, of course, died years before (at the same time her boyfriend had - Norman had poisoned them) but Norman had always felt guilty about her death. He attempted to keep her alive in his own memory and this eventually manifested itself in a physical form when he would take on his mother's personality in order to further the illusion that she was still alive.
Norman was taken to a mental institution where it became evident that the "mother half" of his mind had completely overtaken him.
Norman was portrayed by Anthony Perkins in Psycho, Psycho II, Psycho III and Psycho IV and by Vince Vaughn in Gus Van Sant's 1998 version of the original.