Played By: Anthony Perkins (the whole film series), Henry Thomas (Young Norman in Psycho IV), Vince Vaughn (in Psycho 1998)
- Adorkable: An awkward, shy momma's boy... at first.
- Affably Evil: When running a motel, one needs to be a people person.
- Anti-Villain: As he notes during his conversation with Marion Crane on private traps, "I was born into mine. I don't mind it anymore".
- Ax-Crazy: When the mother side of his personality is in control, brutally stabbing anyone she needs to kill over and over again.
- Bad Liar: Although surprisingly enough, his stuttering and incessant chewing goes some way in convincing Arbogast that he had nothing to do with Marion's disappearance.
- Being Evil Sucks: For the Norman personality, going through extreme amounts of stress and anxiety covering up the murders, as well as dealing with his guilty conscience.
- Beware the Nice Ones: He may be the Trope Codifier. He really a nice and caring young man, but his Split Personality is the psychotic one that takes over.
- Cartwright Curse: Connie (from Psycho IV) is the only one of Norman's love interests who escapes a tragic fate.
- Creepy Crossdresser: When his mother personality takes over.
- Cute and Psycho: Rare male example. His boyish charm and poor social skills can easily throw off the viewer as to his true nature.
- A Date with Rosie Palms: Subtly implied in the original, and flat out shown in the remake.
- Dark and Troubled Past: Father died when he was five years old, leaving him in the care of an overbearing and somewhat incestuously inclined mother, who would emotionally abuse and degrade him.
- Doom Magnet: All of his love interests die as a result of getting too close to him.
- Driven to Madness: By his domineering mother, no less.
- Driven to Villainy: When his mother takes a lover and continues in bullying him.
- Extreme Doormat: To his mother, who deliberately made him dependent upon her after his father's death.
- Freudian Excuse: The abuse he was subject to by his mother when he was young.
- Go Mad from the Isolation: His mother prevented him from interacting with many people, causing him to become strange.
- Gollum Made Me Do It: The last scene of the film is his mother personality plotting and scheming to blame Norman for the murders.
- Hidden Depths: He's shown to be somewhat of a nihilistic philosopher during his brief interactions with Marion Crane.
- I Just Want to Be Loved: He really does want a woman in his life, but his unfortunate circumstances always prevent that from happening.
- Insane Equals Violent: His Split Personality makes him kill every time it takes over.
- Knife Nut: As his mother. All of the murders are committed with a large kitchen knife.
- Kubrick Stare: Perhaps the most grim and soul destroying one in cinematic history.
- Loners Are Freaks: As a result of being isolated from society, he's developed some serious problems.
- Momma's Boy: "A boy's best friend is his mother."
- Mommy Issues: His murderous split personality is due to being emotionally dependent upon his mother since his father died at five years old.
- Nice Guy: When Mommy doesn't take over...
- Oedipus Complex: Norman's mother deliberately isolated her five-year-old son from the outside world and made him utterly dependent on her after Mr Bates' death. Naturally enough, the twelve-year-old, completely co-dependent Norman then reacted rather badly to her remarriage.
- The Peeping Tom: In the parlor and hidden behind a painting, is a hole that looks into Cabin 1. He uses it to look at Marion Crane and Maureen Coyle.
- Psychopathic Manchild: His bedroom looks exactly like a child's room, with toys and everything still in place. He also has a book made of pornographic images designed as a coloring book.
- Reluctant Psycho: In Psycho II, Psycho III and Psycho IV.
- Serial Killer: In Psycho II, he is revealed to have killed seven people before being captured at the end of the first film.
- Sex Is Evil and I Am Horny: When Norman finds himself attracted to women (such as Marion Crane), the "mother" side of his personality lashes out and seeks to rid him of his sinful urges by way of murder.
- Split Personality: Norman and his internalized mother.
- Split Personality Takeover: At the end of the first film. In the words of the psychiatrist: "Norman Bates no longer exists". He gets better in the sequel, however.
- Straw Nihilist: During his conversation with Marion, he expresses a bleak view of life as a trap from which he doesn't even try to escape.
- Sweet Tooth: He's frequently seen with a bag of candy.
- Sympathetic Murderer: He's a good guy , but his dark side is too strong for him to control and have a normal life.
- Talking to Themself: His mother has been dead for years, but he pretends he's still talking with her.
- Taxidermy is Creepy: He keeps a roomful of stuffed birds adjacent to the motel office. And the film's great twist is that his "mother" is actually just a preserved and stuffed corpse.
- They Look Just Like Everyone Else: He looks like an awkward young man, but he's really a deranged Serial Killer.
- Tragic Villain: Although one with an ultimately happy ending, provided you see Psycho IV as being canon.
- Villain Protagonist: After Marion's death, the film rotates between him and her sister as primary protagonists.
- Wicked Cultured: Norman is devotee of Beethoven. While searching his room in the first film Lila notes a record of Symphony No. 3 ("Eroica") on his turntable, and in Psycho II he plays the Moonlight Sonata on the piano.
- Woobie, Destroyer of Worlds: He just wants a normal life, but certain problems prevent that.
Played By: Janet Leigh (in Psycho 1960), Anne Heche (in Psycho 1998)
- Alone with the Psycho: The Trope Namer.
- Anti-Hero: She steals from her company to live a good life with her husband.
- Break the Cutie: Realizes the error of her ways when she talks with Norman.
- Decoy Protagonist: The Trope Codifier. While Sam and Norman both get a decent amount of screen-time in the early stages, the film is almost entirely her story. Then the shower scene happens...
- Kill the Cutie/Heel Face Door Slam: She decides to return to face punishment for her crimes, but is soon killed by Norman.
- Redemption Equals Death: She would likely have ended up dead either way, but after having dinner with Norman (and just before her fatal shower) she decides to return the stolen money to her employers and face the music.
- Sacrificial Lion: Most famously, the film spends the first half detailing her motivations and conflicts, to make it more horrifying when Norman slaughters her.
- Stealing from the Till: Her primary conflict is stealing money from her place of business to help pay off her lover's debts.
Lila Loomis, née Crane
Played By: Vera Miles (in Psycho 1960 and Psycho II), Julianne Moore (in Psycho 1998)
- Ambiguously Evil: She Took a Level in Jerkass and constantly threatens Norman, but she's entirely right in questioning his sanity, making her character ambiguous.
- Asshole Victim: In Psycho II, her actions in the sequel before her death might have been good intentioned in a way, but otherwise still amoral and vindictive towards a man who paid his debt to society.
- Best Served Cold: In Psycho II. She desires swift vengeance on Norman because she believed he slipped through the justice system.
- Cruel and Unusual Death: Impaled through the mouth with a kitchen knife in Psycho II.
- Face-Heel Turn: She was originally the hero of the first film, but the sequel has her become the antagonist trying to ruin Norman's life out of spite.
- Gone Horribly Right: Her plan to drive Norman insane again in the second film goes off very well. Unfortunately, she wasn't counting on Mary becoming sympathetic towards Norman, and definitely didn't foresee Emma Spool messing everything up.
- The Hero: In the first film only. Unfortunately, she becomes a villain in the sequel.
- Hero Antagonist: Towards Norman, in Psycho and Psycho II, however, it's subverted in Psycho II, as the Antagonist side of this trope outweigh the Hero part despite Lila still fulfilling the same trope.
- Inspector Javert: A non-cop version. Still hounds Norman and views him as the irredeemable murderer after he's been released from the mental institution in Psycho II.
- Jerkass Has a Point: In Psycho II, although she does not give Norman a chance for the murder of her sister, in the opening courtroom scene, she was correct that usually the justice system would not give criminals convicted of first degree murder a light sentence of being released back into society to reintegrate, which is why Lila in the second film counts as a Well-Intentioned Extremist.
- Nice Job Breaking It, Hero/Nice Job Fixing It, Villain: Thanks to her desire for revenge on Norman she caused him to return to his psychotic ways.
- Not So Different:
- Seeing as how Lila treats her daughter in Psycho II, she has more than a few similarities to the mother that drove Norman Bates insane.
- And, of course, there's the fact that she sets everything up to make Norman go insane again. Sure, she has a reason for not liking him because he killed her sister and several other people, but to attempt to send him back to the asylum and possibly kill again is just wrong.
- Revenge Before Reason: In Psycho II. She feels that Norman didn't get punished for her crimes and goes on a crusade to ruin his life. However, she breaks numerous laws in her quest, bringing her own death on herself.
- Relationship Upgrade: She married Sam Loomis between Psycho and Psycho II.
- She Who Fights Monsters: In Psycho II. Her obsession to avenge the death of her sister against her murderer slowly begins to corrupt her, causing her to Took a Level in Jerkass by being amoral in her actions and even allowing murders not committed by Norman to be pinned on him anyway.
- Sudden Sequel Death Syndrome: Despite surviving the horrors of the first film, she ends up killed in the second.
- Tautological Templar: In Psycho II, she uses amoral methods to bring down Norman. These methods involve driving a reformed criminal back into insanity and murdering a lot of innocent people.
- Tempting Fate: She constantly says that Norman is a psychopath who hasn't changed. She's proven right in the end after her revenge had a part in driving Norman back into evil.
- Took a Level in Jerkass: In Psycho II. In the first movie, she was a polite but determined woman who wanted to find out what happened to her sister. In Psycho II she tries to amorally drive Norman insane again out of revenge.
- Vigilante Woman: In Psycho II, when she decides to take the law to her own hands to apprehend Norman herself after feeling the courts "protect criminals, not their victims," when Norman was released and declared sane.
- Well-Intentioned Extremist: In Psycho II. Aside from the fact that her attempts to drive Norman insane again to get him recommitted are a result of avenging her sister's death, it also seems out of protecting any other potential victims (or as she quotes them to be "an innocent public") out of harm's way of a "homicidal maniac" (also quoted by her in the opening courtroom scene) in case if he ever relapsed back into insanity on his own without any interference from outside parties such as herself if not sooner. Plus, even though Lila did not seem to care if others who are already killed to have their deaths pinned on Norman anyway, it could be possible Lila saw them as necessary Sacrificial Lambs to bring, what she see it as, a Karma Houdini murderer to justice.
- Widow Woman: In Psycho II, where it's revealed Sam Loomis, whom she married after the events of the first film, has died before the events of the second film.
Norma Bates, née Spool
Played By: Olivia Hussey (in Psycho IV)
- Abusive Parents: Always yells at her son and keeps him away from women.
- Asshole Victim: She was an abusive monster who caused all the hell in Norman's life. Nobody feels bad when we learned that she was killed and preserved as a corpse by Norman.
- Big Bad/Bigger Bad: She's established as the biggest problem in the series. At least in Norman's psyche.
- Evil Matriarch: Though ''Psycho IV downplays this.
- Evil Old Folks: She abused Norman all his life and still haunts him from beyond the grave.
- Hate Sink: Without revealing any spoilers, she is established as a sick person before anyone meets her.
- Incest Subtext: It was confirmed that she did sexually abuse Norman.
- Jerkass: All we know about her is that she's very angry.
- Jump Scare: Her first appearance physically is seeing her corpse spun towards the camera.
- Karmic Death: She's killed by the very son she tormented and left a bloody husk Norman made with his taxidermy skills.
- Manipulative Bitch: Even beyond the grave she continues to torment Norman.
- Mummies at the Dinner Table: In Psycho. Norman preserves her corpse as best he can and keeps her in the master bedroom, hiding her in the fruit cellar when anyone comes snooping around.
- My Beloved Smother: Part of Norman's backstory is that she dominated him and forced him to become co-dependent after his father died. Not to mention her bullying behavior during the film. Or at least, her behavior as Norman remembers her, anyway.
- No Indoor Voice: She's always yelling at her son.
- Obviously Evil: Her first scene involves her screaming at Norman from her house, with Norman saying how she always puts him down.
- Peek-A-Boo Corpse: In Psycho. It serves as the twist when we see that she's been preserved by her own son.
- Posthumous Character: We only learn more about her after it's revealed she's been dead for years. Otherwise, Norman's flashbacks only show her personality.
- The Reveal: She's revealed to be nothing but a corpse physically, but her personality is inside Norman due to all the abuse he's suffered under her.
- The Unseen: She's never seen until the end of Psycho. But she is often heard either by Norman or anyone not near the two in the first movie.
- Unwitting Instigator of Doom: Thanks to her abuse, she caused Norman to become a mentally unstable Serial Killer.
- Walking Spoiler: She plays a very important part to Norman's character.
Mary Samuels (real name Loomis)
Played By: Meg Tilly (in Psycho II)
- Dead Person Impersonation: Impersonates Norman's mother with a robe, a wig and the kitchen knife in hope of stopping him from going insane again. It doesn't end well for her.
- Heel-Face Turn: She grows genuinely convinced of Norman's newfound sanity and at some point doesn't want to help her mother make him insane anymore, however, after discovering Lila's dead body, she fully accept Lila was right all along about Norman and gets killed just after believing into it.
- Hero Antagonist: Was in on Lila's plan to bring Norman to justice and have him incarcerated for good. Subverted when she starts to sympathize with Norman and later turn against her mother's intentions to have him arrested again. However, after discovering Lila's body in the pile of coal in Norman's cellar, Mary firmly grasped completely on this trope only to seconds later be shot by the police for her attempt on Norman's life.
- Kill the Cutie: She is shot dead by the police after an unlucky and tragic chain of reactions.
- Nice Girl: She acts kind and gentle towards both Norman and her jerkass mother when she doesn't have to.
- Sympathetic Inspector Antagonist: In contrast her mother's Inspector Javert, Mary, despite being in on her mother's plans, is sympathetic towards Norman and later turn against her mother's mission to have Norman re-arrested and re-committed, until seeing her mother's corpse convinces her Lila was right all along it seems.
- Vigilante Woman: At first, she was involved with her mother's Well-Intentioned Extremist plans, but later turn against Lila after becoming convinced of Norman's newfound sanity, but later plays this role straight for a minute in the climax after discovering her mother's dead body.
Played by: Diana Scarwid (in Psycho III)
- Accidental Murder: Norman accidentally makes her fall down the stairs to her death when he sees the spirit of his mother.
- Bath Suicide: She attempts to kill herself in the motel bath tub, but Norman saves her.
- Broken Bird: She suffers from extreme depression that causes her to be Driven to Suicide.
- Cruel Twist Ending: As soon as she turns her life around and offers Norman a chance to do the same, she dies by accidentally falling down the stairs.
- Driven to Suicide: She nearly kills herself, but Norman rescues her.
- Heel Face Doorslam: Just when she finally gets over her troubles and begins a relationship with Norman, she dies completely by accident.
- Interrupted Suicide: When Norman comes into her room, his good personality returns just in time to save her, preventing history from repeating itself.
- Kill the Cutie: By accident. Or was it Mother's spirit?
- Love Redeems: She realizes that she is in love with Norman and vows to help him get better. Sadly, tragedy strikes soon after.
- Ms.Fanservice: The audience gets a perfect view of her body in the bath tub.
- Naughty Nuns: She works as a nun, but slowly develops feelings for Norman. She's also the third film's Ms.Fanservice.
- No Good Deed Goes Unpunished: After finally realizing her true feelings for Norman, she dies completely by accident.
- Nice Girl: She shows nothing but respect for everyone around her.
- Nun Too Holy: She's a nun who wants to kill herself.
- Single Woman Seeks Good Man: She falls for Norman because he is a so caring towards her. At least when he's not under control of his Split Personality. She even tries to save his soul because she knows he's a good man deep down.
- Troubled, but Cute: She's very attractive, but needs a lot of help conquering her inner demons.
Played by: Claudia Bryar (in Psycho II)
- Affably Evil: She's very approachable when she's not killing people to defend Norman.
- Asshole Victim: Norman kills her with a Shovel Strike at the end of Psycho II.
- Beware the Nice Ones: She may seem like a sweet old lady, but she's the real killer of the second film.
- Bigger Bad: Of the original trilogy, through kidnapping Norman as a baby and killing Norman's biological dad, she's indirectly responsible for her sister to abuse Norman that turned him into a serial killer that lead to the events of the first film and its sequels.
- Evil Old Folks: She performed all the murders of the second movie in order to drive Norman back to her.
- Insane Equals Violent: She's really an escaped mental patient who wants Norman to be her son. So naturally this makes her violent because she kills multiple people.
- Karma Houdini Warranty: She got away with attempting to steal Norman and murdering people for a very long time. That is until Norman killed her in a fit of rage.
- Karmic Death: Killed by the very child she was trying to dominate.
- Knife Nut: She is the knife-wielding murderer in Psycho II.
- Mummies at the Dinner Table: "Replaces" Norman's mother at the end of Psycho II and in Psycho III. Norman stuffs her body at the beginning of Psycho III.
- My Beloved Smother: Subverted. She claims she is Norman's mother and tries to raise him exactly the same way his real mother did.
- Parental Substitute: Sort of. In the most horrible way imaginable actually. She "replaces" Norman's mother as a mummy Norman talks to.
- The Reveal: She is Norma's sister.