Paranoia is an interesting topic in film, often exploring the different themes and conditions that tend to set humanity on edge. While many of the most compelling psychological horror movies do have elements of paranoia incorporated into their plots, it is rare that a film truly dives into the matter. This is not the case with all movies, as films like Black Swan and Rosemary's Baby take their elements of paranoia to the extreme.

Though many paranoia films are the best movies of all time. Regardless, they all explode with paranoia at some point or another, leaving both the main character and the viewer wondering both what is real and what will happen next.

10 Unsane (2018)

The Psychological Thriller Shot On An iPhone 7

Starring Claire Foy of The Crown fame, Unsane is a unique psychological thriller that was shot entirely on an iPhone 7. Following a woman named Sawyer who has recently moved to a new town to run away from a dangerous stalker, she attempts to make a normal life for herself. However, when Sawyer is committed to a psychiatric hospital after inadvertently g a form, things quickly begin to fall apart around her.

Cramped and horrific with its portrayal of paranoia, Unsane takes a set of very real anxieties and shows how women's fears can often be ignored. This sort of disregard comes not only from the police but the psychiatric institution that holds Sawyer captive as well. The danger is palpable in this movie, making for a thrill ride that rarely lets up for long enough to let the viewer rest.

9 Black Swan (2010)

Swan Lake Is Taken To A Whole New Level

Revolving around a production of Tchaikovsky's Swan Lake, Black Swan shows the world of ballet in a terrifying and competitive light. The story focuses on the dynamic between two ballerinas, Nina and Lily, who compete for the lead role, a dual character that must embody both dark and light qualities as Odile and Odette. However, when one ballerina must play both, it is Nina who is initially a perfect fit for the Swan Queen, while Lily would be perfect for the Black Swan.

As the film progresses, the line between what is real and what is a product of Nina's mind quickly becomes blurred. This includes her impression of Lily and whether the two are the same person or different, making for a confusing but interesting depiction of the ballet itself as the movie plays out. Desperation and obsession mix with the distinct paranoia that Nina's dream and identity are being taken away from her, making for an exciting thriller.

8 Bug (2006)

Conspiracies & Delusions Abound Between The Main Characters

Another film that initially begins with a terrible stalking, Bug is a film steeped in mutual delusion and conspiracy. After escaping her abusive ex-husband, a waitress named Agnes takes shelter in a dilapidated motel where she spends her time drinking with her friend R.C. She soon finds herself striking up an unusual friendship with a man named Peter Evans, who begins living with her inside her motel room.

Bug initially premiered at the Cannes Film Festival, even winning an award from the International Federation of Film Critics.

When Peter wakes one night having found a bug in bed, he tells Agnes that he suffers from what he thinks are invisible bugs crawling through his body. If this weren't enough, he also believes that he is being followed, explaining an elaborate conspiracy with him at the center. As things progress, Agnes begins to share his delusions, telling the tale of two people connected by dangerous fantasies.

7 Perfect Blue (1997)

This Animated Film Inspired Many Psychological Thrillers

A Japanese animated classic, Perfect Blue is one of several projects worked on by the incredible director Satoshi Kon. The film follows a member of an idol group who makes her transition to becoming a full-time actress after leaving her life of singing behind. As her life becomes more and more stressful, she is haunted by the image of another version of herself who remained an idol.

Perfect Blue takes the paranoia of losing one's self and being replaced and pushes it to its natural breaking point. Reality is broken, creating a world where paranoid delusion is the norm and the line between what is real and what isn't is nonexistent, only serving to make the film even more tense. Perfect Blue served as inspiration for several other films, most notably by director Darren Aronofsky, who created Requiem for a Dream and Black Swan.

6 The Machinist (2004)

Christian Bale's Performance Is One Of His Best

The Machinist is a movie that explores the relationship between sleep and paranoia, following Trevor, whose insomnia has kept him from sleeping comfortably for an entire year. This lack of sleep not only leads Trevor to be more paranoid but also results in him becoming emaciated as well. Trevor's fears really begin to come into play when mysterious sticky notes begin to appear on his refrigerator out of nowhere.

As Trevor's paranoia grows, so does the uncertainty about what he is actually seeing. With writing that begins slowly and builds until the tension is unbearable, The Machinist knows exactly when to speed up and when to pull back, creating an ebb and flow that keeps the film moving. The story certainly keeps the viewer on their toes, with everything coming full circle by the time the credits roll.

5 The Manchurian Candidate (1962)

Frank Sinatra Stars In This Black And White Classic

The Manchurian Candidate is a political thriller with terrifying implications, taking place during the Korean War. When American military man Raymond Shaw is captured by the enemy, he is transported to China. It is here that he is programmed by enemy soldiers to be a sleeper agent, triggered to kill by the suggestion of playing the card game solitaire.

This film is currently saved in the United States National Film Registry, as it is seen as holding enough cultural and historical significance.

As the movie progresses, Bennett Marco, played by Frank Sinatra, tries his best to deprogram Shaw in an attempt to not only save him but those around them as well. Though the paranoia in The Manchurian Candidate is more subdued in some respects, it comes to life in the fear built around the movie's political turmoil. These politics reflect real-life fears, ones that never truly go away, something that makes the viewer feel even more paranoid.

4 The Lighthouse (2019)

Robert Eggers' Black And White Film Is Captivating

When two men are tasked with taking care of a lighthouse together, there is initially no cause for alarm as The Lighthouse begins. However, things in this film are rarely what they seem. As Ephraim Winslow s Thomas Wake in this endeavor, things begin to unravel as it becomes increasingly clear that, for some reason or another, Thomas is worshiping the light at the top of the lighthouse.

It is the isolation that brings the downfall of these two protagonists, taking the extended periods of loneliness they must endure and showing how this affects their mental state. The more Ephraim falls into the same delusion as Thomas, the harder it becomes to distinguish what is real and what isn't. This hits its breaking point when the two lighthouse keepers begin to turn on each other, giving in to the paranoia that solitude brings them.

3 Rosemary's Baby (1968)

Gaslighting & Paranoia Are The Center Of This Horror Film

Rosemary's Baby is a terrifying look into the life of Rosemary Woodhouse, a woman who initially celebrates upon learning she is pregnant. At the beginning of the film, she prepares for the coming of her child with an excited demeanor, as any expectant mother might. However, she slowly learns that the people around her aren't who they seem to be, with even her husband being part of a greater conspiracy to bring about the Antichrist.

The slow build of Rosemary's Baby is precisely what makes the film so spectacular, taking the ordinary life of one woman and revealing that her worst fears are being realized. As the paranoia builds, Rosemary learns that she can only rely on herself. There is no one she can trust, something that makes the movie itself so instantly terrifying.

2 The Thing (1982)

John Carpenter's Horror Film Is One Of The Greatest Paranoia Films

Taking place in a research facility in the frigid wilds of Antarctica, The Thing details what should be an exciting discovery. It is here that a new alien lifeform is discovered, only known as "The Thing." This breakthrough discovery is turned into a horrific nightmare when it is discovered that The Thing can assimilate any and all under its power, killing the researchers in the process.

The Thing is based on a 1938 novella titled Who Goes There? written by John W. Campbell Jr.

The paranoia truly comes as the characters try to deduce who has become a part of The Thing and who hasn't, inviting the viewer in to decide as well, leaving people debating the ending decades later. The best part is that nothing is certain, and even the main character, R. J. MacReady, is cast under suspicion. The Thing is an incredible exercise in building tension and mistrust, just as much of a mystery movie as it is a horror film.

1 The Conversation (1974)

This Francis Ford Coppola Film Is Paranoid At The Very Core

Despite the simple name of this film, The Conversation is an intriguing story that begins when Harry Caul and his team are hired to eavesdrop on a couple. However, he hears something in the recording that initially gives him pause, launching him into a full investigation into the woman, her lover, and the people surrounding them. Harry finds himself flooded with information, eventually insisting that a murder must have taken place.

One would initially think that the paranoia in this film would come from the couple being listened to, but it is actually Harry himself who is the subject of this paranoia. The breakdown that develops as a result of this one recording is intriguing to watch, taking the viewer along his downward spiral. This, coupled with a somewhat hopeless ending, makes The Conversation an incredible entry into the world of this subgenre of films.