The Signal starts as a road trip movie involving three college students tracking a mysterious hacker, but it quickly descends into a disorienting sci-fi mystery after they are attacked and one of them wakes up in a strange, isolated facility. The film plays with themes of reality, identity, and paranoia, keeping the audience guessing about what is happening and why. While less focused on time loops or paradoxes than some other films on this list, it shares a sense of escalating mystery and a slow reveal of a larger, unsettling sci-fi concept that pulls the rug out from under the characters.

Donnie Darko is a cult classic sci-fi mystery that blends elements of suburban drama, psychological thriller, and temporal paradox. A troubled teenager, Donnie, is visited by a figure in a terrifying rabbit suit named Frank, who tells him the world will end in 28 days. This event sets off a chain of bizarre occurrences involving time travel, parallel universes, and destiny. The film's ambiguous narrative, rich symbolism, and atmospheric tone have led to extensive fan theories and discussions, making it a fascinating and enduring piece of indie cinema.

This film explores the classic time travel trope of altering the past and its unforeseen consequences with a darker, more dramatic tone. Ashton Kutcher plays a young man who discovers he can travel back in time to inhabit his childhood body and change events. However, each change results in drastically different, often worse, timelines in his present. The film delves into themes of destiny, consequence, and the desire to fix past mistakes, showcasing how seemingly small alterations can have catastrophic ripple effects, much like the scientific concept it's named after.

Source Code uses the concept of a time loop within a high-stakes action thriller framework. Jake Gyllenhaal plays a soldier who wakes up in the body of an unknown man, discovering he is part of a government program that allows him to relive the last eight minutes of a victim's life aboard a commuter train that was bombed. He must use these repeated eight-minute cycles to identify the bomber. Directed by Duncan Jones (Moon), the film is a smart, fast-paced mystery that blends sci-fi concepts with intense suspense and a compelling human element.

Shane Carruth's follow-up to Primer, Upstream Color, is a far more abstract and experimental film, focusing less on plot mechanics and more on themes of identity, trauma, and connection through a mysterious biological organism. While not a traditional narrative, its intricate structure and reliance on visual and auditory storytelling create a deeply immersive and thought-provoking experience. It's a film that washes over you, inviting interpretation rather than providing easy answers, and shares Primer's commitment to unique, challenging sci-fi concepts.

Time Lapse centers on three roommates who discover a mysterious machine in their neighbor's apartment that takes pictures 24 hours into the future. Initially using it for personal gain, they soon find themselves trapped by the camera's predictions, forced to act out the events in the photos to avoid paradoxes or worse. This contained sci-fi thriller explores themes of determinism, free will, and the ethical implications of knowing the future, creating a tense and engaging narrative as the characters' lives spiral out of control.

From the directing duo Benson and Moorhead (who also appear in the film), The Endless is a cosmic horror/sci-fi hybrid that delves into cults, time loops, and unexplained phenomena. Two brothers return to the UFO death cult they escaped years ago after receiving a mysterious tape. They soon discover the cult's beliefs are tied to something far stranger and more terrifying than they could have imagined. The film builds a unique mythology and atmosphere, blending elements of mystery, horror, and existential dread, making it a compelling watch for fans of cerebral genre fare.

Blending relationship drama with subtle sci-fi, The One I Love follows a struggling couple, played by Mark Duplass and Elisabeth Moss, who go on a weekend retreat to save their marriage. The therapist suggests a specific property, and once there, they discover something bizarre and unsettling about the guest house that forces them to confront warped versions of themselves and their relationship issues. Like Coherence, it uses a confined location and a strange phenomenon to explore complex human dynamics, resulting in a film that is both funny, poignant, and deeply strange.

Based on the classic Robert A. Heinlein short story '—All You Zombies—', Predestination is a mind-bending journey through time, identity, and paradox. Starring Ethan Hawke and Sarah Snook in a truly transformative performance, the film follows a Temporal Agent who travels through time to prevent major crimes. His final mission leads him to a mysterious man whose life story is intertwined with his own in ways he couldn't possibly imagine. The film is a complex puzzle box that explores themes of fate, free will, and self-creation, anchored by incredibly strong performances.

Triangle is a British psychological horror film that takes the concept of a time loop and twists it into a terrifying, inescapable nightmare at sea. A group of friends on a yacht are rescued by a mysterious, deserted ocean liner after a storm, only to find themselves trapped in a horrifying cycle. The film constantly reinvents its premise, adding layers of mystery and dread as the characters try to understand the rules of their reality and escape the loop. Its intricate plot and chilling atmosphere make it a standout in the time loop subgenre, keeping viewers disoriented and hooked until the very end.

This Spanish gem, directed by Nacho Vigalondo, is a taut and suspenseful time loop thriller that shares Coherence's strength in using a contained setting to maximum effect. A man spots something strange in the woods with his binoculars and, investigating, accidentally steps into a time machine that sends him back just an hour. The film expertly plays with cause and effect, paradoxes, and the unsettling feeling of being trapped in a loop of your own making. It's a lean, efficient narrative that keeps you guessing and is a perfect example of clever sci-fi storytelling on a modest scale.

Often cited as one of the most challenging time travel films ever made, Primer is the debut feature of former mathematician and engineer Shane Carruth. Made on a shoestring budget of only $7,000, the film follows two engineers who accidentally discover time travel. Its brilliance lies in its hyper-realistic depiction of the science and the complex, non-linear narrative structure that demands multiple viewings to even begin to unravel. Carruth not only wrote, directed, and starred in the film, but also composed the score and handled the editing, showcasing a singular vision that makes it a true indie sci-fi landmark.

Let's start with the film that set the standard for this list! Coherence is a masterclass in low-budget, high-concept sci-fi. Filmed mostly in director James Ward Byrkit's own house, the movie thrives on its naturalistic dialogue and escalating tension as a group of friends gather for a dinner party on the night a comet passes overhead. What begins as strange occurrences outside quickly turns into a reality-bending nightmare inside. The actors were given outlines and character motivations but largely improvised their dialogue, contributing to the incredibly authentic and unsettling atmosphere. It's a fantastic example of how clever writing and committed performances can create profound cosmic horror and psychological thriller without needing a massive budget.