"I find Hitchcock's films to be a bed of paradoxes and ambiguities in which identity is questioned and explored" (297), Lucretia Knapp writes in her essay "The Queer Voice in Marnie." Indeed, Hitchcock often deals with the matter of identity in his films, as his characters struggle to establish or reestablish their selves. In this vein, he frequently utilizes costuming to demonstrate the changeable nature of identity. In Marnie, the audience encounters a young woman who clearly claims the identity of a thief, but lacks any real understanding of herself beyond her kleptomania and surface reactions to deep-seated fears. Vertigo explores the identities of two characters—Scottie and Judy/Madeleine—both of whom maintain rather unstable and undefined senses of self throughout the story. A case of mistaken identity forms the basic plotline of North by Northwest, in which an innocent man finds himself playing a role determined by other people through no fault of his own. In these three films, Hitchcock presents identity as a slippery, fluid concept and—because identity often represents nothing more than a fragile façade—he simultaneously examines the primal human fear of nothingness or a lack of the essential core self.

The three films all emphasize the changeable nature of identity, showcasing characters that repeatedly assume and discard various personas. In, for instance, Knapp maintains that "from the outset of the film... Marnie's identity is problematized" (300). Hitchcock first introduces the audience to Marnie by focusing the camera on her canary yellow purse. This image shifts to an office setting where Mr. Strutt utters the film's first spoken word: "robbed." As Knapp suggests, "[t]his fetishized object signifies Marnie's 'problem' (her thievery) and her shifting identity (her changing costume)" (300). Marnie's only consistent identity throughout the film remains that of a thief.

Her actions following the robbery further demonstrate the fluidity of identity. Marnie retains a collection of several social security cards; for her, changing identities is as simple as switching purses and adopting a new alias. As Strutt informs the police of the details of the robbery and "Marion Holland," the reality of Marnie as "a pretty girl with no references" emerges. Her lack of references contributes to the idea of a "problematized" identity. No one knows Marnie, just as she lacks knowledge of herself. In addition to attaining money in order to hopefully secure her mother's approval, Marnie's multitude of lies and pattern of stealing and running away function to keep people away and keep herself distracted from facing her own personal depths.

Identity poses a problem in Vertigo as well, particularly in the characters of Scottie and Madeleine/Judy, both of whom lack clear, definable selves. The theme of wandering—mentioned so frequently throughout the film—reiterates the two main characters' lack of self-understanding. Elster says of Madeleine, "[s]he wanders; God knows where she wanders." As Scottie begins tracking her, he himself becomes a wanderer. The idea of wandering connotes a lack of purpose and a sense of aimlessly searching for an unidentifiable something. As wanderers, the two main characters likely seek self-knowledge, but have no idea where to begin their quest. Wood links the concept of wandering with Scottie's "metaphoric suspension" throughout the film in his essay "Male Desire, Male Anxiety." He discusses the vertigo Scottie experiences from atop Midge's stepladder as an example of both this suspension and an unstable sense of self, proposing that "[a]lso relevant here is the question of identity: the fluidity, the lack of definition suggested by the range of names Stewart's character accumulates in the course of the film" (230). Various people know Scottie by different names, suggesting a lack of continuity in his identity.

The identity of Novak's character also remains highly problematic through the course of the film. She obviously exists as two separate women, first playing Madeleine and then settling back into Judy, but the film also connects her identity to Carlotta Valdez. The issue of possible possession of the living by the dead (first with Carlotta and Madeleine, and later with Madeleine and Judy) further complicates the concept of identity in Vertigo.

North by Northwest also imparts the idea of identity's slipperiness as Grant's character loses his identity as Roger Thornhill and comes to accept that of George Kaplan. In his essay, "North by Northwest," Cavell notes that, "[i]t happens that in the fiction of this film this new fictional identity is imposed by reality" (252). The film explores how other people function to either confirm or deny an individual's proposed personhood. When Vandamm and his cronies refuse to corroborate Grant's self-identification as Roger Thornhill, he essentially has no recourse. He expresses this lack of options when he makes the statement, "I don't suppose it would do any good to show you a wallet full of identification." Even his government-issued credentials fail to secure his identity. Eventually Thornhill adopts the persona of Kaplan for himself, interacting with the hotel staff as Kaplan and offering the name George Kaplan to the clerk at United Nations ("My name? Kaplan. George Kaplan.") Thornhill's inability to keep his identity intact reveals its instability and vulnerability.

Along with the idea of identity as slippery and fluid, Marnie, Vertigo, and North by Northwest all channel performance theory, which views identity as a construct or façade carefully created by each individual. As a thief who regularly changes names, locations, and hair colors, Marnie certainly creates and recreates her persona. Early in the film, the audience witnesses her washing out her black hair dye, and therefore washing away her identity as Marion Holland, and reemerging as Marnie Edgar. In her first appearance as herself, Marnie wears a pale green suit with a green scarf. Like the motif of green in Vertigo, her clothing choice seems to represent rebirth or resurrection. Marnie realizes the fragility of her façade (along with the audience) at the race track when a man recognizes her as Peggy Nicholson from Detroit. Likewise, Strutt recalls her as his burglar at the party celebrating her marriage to Rutland. While Marnie maintains the ability to create for herself a new identity, this process fails to entirely erase her actions under other personas. After returning from their honeymoon, Mark instructs Marnie on how to play the role of a loving wife and tells her "[f]or the present all we've got is the façade. And we've got to live it." Mark's statement refers to the façade of a happy marriage, but his words also apply specifically to Marnie's sense of identity. Because she lacks self-understanding, all Marnie ever has is the façade. And so she lives it.

In Vertigo the idea of identity as scripted emerges forcefully in the characters played by Kim Novak. Madeleine represents nothing more than a façade for her entire presence in the film. Scottie hatefully acknowledges the ruse of her existence as he terrorizes Judy in the bell tower about her role in Elster's scheme: "Did he train you? Did he rehearse you? Did he tell you exactly what to do, what to say?" Judy's successful portrayal of Elster's wife exposes identity as nothing more than a set of nuances of appearance and mannerism that another individual can easily adopt if properly instructed. Hitchcock utilizes several mirror shots to repeatedly show Judy in double, again highlighting the idea of identity as a façade. The film's makeover sequence underscores the importance of costume and makeup, which functions here to simultaneously conceal and reveal identity. As Novak undergoes the makeover process at Scottie's insistence, her identity as Judy Barton disappears more and more, while her identity as Madeleine becomes increasingly obvious. Ironically, Judy seems to play Madeleine—a role she had to practice for—more convincingly than she plays herself. When she pulls her Kansas and California driver's licenses out to show Scottie, it almost seems as though she needs to persuade herself of her identity as well.

Cavell identifies one of the themes in North by Northwest as "the nature of identity and the theatricality of everyday life" (252). He further identifies Vandamm and the Professor as stand-in directors in the film, noting how they "create scenarios and make up parts for people" (252). Vandamm makes a couple of comments throughout the film that relate to everyday theatrics. When Thornhill mentions his theatre tickets as a reason to leave Townsend's estate, Vandamm tells him that "[w]ith such expert playacting you make this very room a theatre." Later at the auction he accuses Thornhill of overacting: "Has anyone ever told you that you overplay your various roles rather severely, Mr. Kaplan?" These comments indicate that the nature of identity remains that of a performance, actively put on by the individual.

The film further implicates identity as just a façade in George Kaplan's non-existence. When the Professor reveals Kaplan as a made-up decoy, Thornhill challenges him, saying, "What do you mean? I've been to his hotel room... he has short sleeves and dandruff." In North by Northwest, the mere manifestation of Kaplan remains enough to convince people of his reality and cause trouble for Thornhill, who actually does exist. By failing to exist, Kaplan forces the question of identity; one seemingly need not even exist in order to maintain an identity, therefore identity truly remains nothing more than a façade.

While exposing identity's instability and even ruse-like nature, Hitchcock concurrently hints at the human fear of the self as nothingness. When Mark asks Marnie what she believes in at the racetrack, she replies "[n]othing;" and the theme of nothingness reverberates throughout the film. After she wakes from her nightmare, Mark asks her what it means; Marnie again answers "[n]othing." The majority of the film involves Mark trying to find Marnie's true identity, while she struggles to keep the disturbing incident from her childhood hidden in the depths of her unconscious. Mark implores her to read psychology books, suggesting that she start with The Undiscovered Self. The mention of this text implies Marnie's lack of self-knowledge and her reluctance to explore herself lest she find an undesirable truth or glaring emptiness within.

A sense of lacking infuses Marnie's character, providing one reason for her kleptomaniac tendencies and the frequent shifting of identities they necessitate. Knapp points out that "Marnie functions by constantly assuming and then denying identities. When trying to define Marnie, we can say what she is not but not, exactly, what she is" (301). Mark certainly regards Marnie as an enigma, and she definitely fails to understand herself beyond her surface identity as "a cheat and a liar and a thief." Her sense of nothingness stems from her mother's unwillingness to demonstrate love toward her. During her first trip home in the film, Marnie pleads with her mother: "Why don't you love me, Mama?" Even when her mother speaks of her love for Marnie at the film's climatic end, she remains unable to express this love in any tangible way. This blatant lack pervades Marnie's existence and connects to her inability to secure a consistent identity for herself.

The fear of self as nonexistent permeates Vertigo as well. In "A Closer Look at Scopophilia," Keane suggests that Scottie greatly fears his own nothingness, and this dread explains his strong attachment to Madeleine and his compulsive desire to reinvent Judy in her image: "Harboring the fear that he is himself nothingness, Stewart/Scottie conjured a vision of nothingness and breathed life into it throughout his re-creation of the ghost Madeleine" (246). His fear emerges clearly in his nightmare sequence following the inquest about Madeleine's death. Images of Carlotta conjure up the idea of death and ghostly presences, while Stewart's stumbling movements across a pitch black screen and the picture of his detached head hurdling into a grave convey the penetrative quality of darkness.

Scottie violates Judy significantly by forcing her to become nothingness in his quest to rediscover Madeleine. When she emerges from her bathroom in the gray suit with her newly-dyed blonde hair pinned back, Judy fails to exist, except as the reincarnate of Madeleine. Keane declares that Judy leaps from the bell tower at the film's end because the shadowy figure of the nun embodies Judy's sense of nothingness, or represents "a consummate denial of her existence" (246). Judy only succeeds in proving her existence by ending it.

The concept of nothingness follows Roger Thornhill throughout North by Northwest, first as another identity imposes itself upon him and later as circumstances force him to run from Vandamm as well as the police. When Eve asks him what the 'O' in 'ROT' stands for, Thornhill can only answer "[n]othing." His middle initial's lack of meaning connects well to the overall theme of the human self as possibly nothing. The government agency reflects the sense of the individual as meaningless, particularly when compared to the greater public good. The female representative matter-of-factly concedes to the Professor's decision that they initially shall not intervene of Thornhill's behalf, saying "[g]oodbye, Mr. Thornhill. Wherever you are." The organization clearly views Thornhill as collateral damage; he fails to matter to them, and they therefore regard him as nothing.

Likewise, the scene where Thornhill waits for Kaplan only to meet an attack by a crop-duster plane speaks to the insignificance of the individual and the self as naught. The camera remains zoomed out as Thornhill steps off the bus into the desolate Midwestern terrain; he appears no bigger or more incidental than the fence post by which he stands. Cavell regards this scene as one where "[t]he man undergoes his Shakespearean encounter of nothings—the nothing of Thornhill meeting the nothing of Kaplan—the attack on his identity as it were, by itself" (256). Grant's character survives this attack, which seems to reestablish his identity as Roger Thornhill. Soon after this climatic turn he learns the truth about George Kaplan and Eve Kendall from the Professor; Kaplan's successful destruction and Thornhill's full return to selfhood occur when Eve shoots Thornhill as Kaplan, thus releasing him from his imposed identity. His fear of nothingness dissipates with the removal of the nothingness of Kaplan.

For Hitchcock, identity simultaneously exists as a fluid concept, a mere façade, and a human being's frail protection from realization of the self as nothing or an essential lack of self. The main characters in Marnie, Vertigo, and North by Northwest often seek to discover or rediscover their identities, and Hitchcock highlights this seeking process for his audience. As the master of suspense, Hitchcock frequently complicates the line between guilt and innocence. Similarly, he expresses the complexity between the closely related concepts of identity and nothingness. Perhaps these three films offer such psychological thrills because they force the audience to question the one entity each human believes belongs rightfully and solely to him/her: the self. By presenting the self and one's identity as corruptible, Hitchcock plays on one of humanity's greatest fears.