Not much is understood about dreams; they may be prophetic, purely symbolic, or even nothing more than a random collection of memories, or any combination of the three, as well as anything else the world of fiction would like to make them. But one thing is for sure- dreams are unique to the individual, tailor-made by our own brains or granted by the Gods, with some of the chaos only being meaningful to the dreamer.
Well, this isn't always true in fictionland. Occasionally, characters will have the exact same dream- or at the very least, the same dream from a different point-of-view. From the location, to the characters, to the "plot", the details will be the same, even if the perspective isn't. They may start out as normal dreams and then have something of a crossover later on, or they may share the dream from the get-go; in the end, the result is the same.
This can usually be chalked up to something supernatural. A prophecy, for example, may need more than one Chosen One- so The Chosen Many will all have the same dream about said prophecy. A character with the power to grant dreams may choose to trap everyone in the same dream, which is especially common if the dream is actually a nightmare. Or, mind-reading characters may be able to experience someone else's dream while asleep.
Whatever the reason, though, the characters have the same dream... and, with these dreams usually being rather important to the plot of the overall story, they'll no doubt remember it when they wake up and come to the realization that the dream was a shared experience. That said, this can also occur in a Dream Episode, with the episode's premise being that all the characters are having a single, chaotic, overlapping dream.
Compare the occasionally-overlapping Dream Land, where dreams aren't just mental, but take place in different realities altogether, one where the characters will occasionally take part in the same dream. Also compare to the Dream Walker, who can enter other people's dreams as an ability, and the Dream Weaver, with the power to alter or grant dreams. But You Were There, and You, and You is a distinct-but-related concept where the cast of a dream is made up of people the character already knows- but who aren't literally having the same dream as the dreamer. Can be faked in a Dream Deception.
- Hamtaro: A staple of every Dream Episode is that at least Laura, Hamtaro and all the other hamsters often make the same dream together.
- Weathering With You: After Hina's Heroic Sacrifice, multiple people report having the same dream of her being taken away to the sky, just before waking up to find the world sunny and warm.
- Tintin: The Seven Crystal Balls: Tintin, Haddock and prof. Calculus all have the same dream of the mummy of Rascar Capac breaking into their room and smashing a soporific-filled crystal ball on the floor.
- Wonder Woman (1987): Diana and Donna talk and realize they are both having the same recurring nightmare about their mother's death, which makes them realize Circe is tampering with their dreams.
- Is often the case in several Foxtrot arcs involving one of the Fox family members having a dream, wherein, if any of the others in the family within the dream, they seem to be experiencing the dream as vividly as the one dreaming is and can even influence their sibling's/parent's dream themselves. It's lampshaded in an arc involving Peter having a dream about The Odyssey while trying to write a report about it; in the first comic in the arc, Jason tells Peter to not include him in any dreams about The Odyssey Peter may end up having. Gilligan Cut to Jason being in Peter's dream anyway, displeased and reaming Peter out.
- The Dark Lords of Nerima: The Dark Lords Ascendant, a sequel to the original story, has the heroes use Pegasus's abilities to connect to those asleep to conjure a mass shared dream for the citizens of Japan in order to directly communicate with them. This is to counter the Big Bad Corrupt Corporate Executive who used his media connections to portray the Sailor Senshi's attack on his headquarters as unjust attack on a honest businessman.
- Dreamscape: The main character is psychic, at first he has to use a machine to share dreams, later he gets the ability to do this by himself. The villain also learns to do this without the machine as part of a plot to kill the President.
- Explorers: Initially Ben is the only one having the recurring dream about flying over a circuit diagram, which turns out to be plans for a force-field generator that doubles as a Reactionless Drive. Later he has another dream, this time showing how to build an oxygen generator — but now his friends, Wolfgang and Darren, are both there as well, which confirms that (as they had already guessed) the dreams are actually messages sent by aliens. At the end, the three — now joined by Ben's Love Interest Lori — have another dream, this one showing the biggest diagram yet...
- Inception - This is the goal of Cobb and his crew, only the shared dream is a scheme to plant an idea in the mind of a powerful executive.
"What's the most resilient parasite? A bacteria? A virus? An intestinal worm? [...] An idea. Resilient, highly contagious. Once an idea has taken hold in the brain, it's almost impossible to eradicate. An idea that is fully formed, fully understood? That sticks."
- In On Body and Soul, the two main characters share several dreams, where they are a deer and a doe living in a snowy forest.
- The Call of Cthulhu: People all over the world have horrifying nightmares and visions of the sunken city of R'yleh. Artists and poets had the clearest and most terrifying visions while average working-class folk experienced none at all. Scientists suffered far more minor visions, but these dreams were enough to spark cults and mania across the globe.
- Carmilla: Subverted, as the protagonist Laura and the title character recognize each other from a shared dream in their childhoods upon first encountering each other. It later turns out, however, that Carmilla is a vampire who used her powers of suggestion on Laura in order to make her remember a dream she's never had and thus to get into her confidence.
- Douglas Coupland: In Girlfriend In A Coma, two characters are detoxing and have a shared dream about the same apocalyptic vision.
- Indexing: People affected by the same Narrative sometimes report dreaming of a place where they all meet.
- The Lord of the Rings: Faramir gets a recurring dream that tells him to "Seek for the Sword that was Broken." On one occasion his brother Boromir has this dream as well, which is one of the reasons why Boromir, rather than Faramir, traveled to Rivendell.
- The Stand: All of the Superflu survivors have recurring dreams of Mother Abigail and Randall Flagg beckoning them to come to either Boulder, Colorado or Las Vegas.
- Tales of the Five Hundred Kingdoms: In The Fairy Godmother, Erotic Dreams shared between two of the characters, is a sign that the Background Magic Field known as the Tradition, is nudging them together.
- The 4400: One episode features a member of the titular group trapping the main characters in a shared nightmare in order to force them to stop fighting each other.
- Angel: In "Orpheus", Angelus and Faith have a shared drug-induced hallucination, after Faith took the drug and lured Angelus into biting her, to incapacitate him.
- Doctor Who:
- In "The End of Time", everyone in the world has the same dream of seeing The Master laughing, foreshadowing him turning all of them into himself.
- In "Amy's Choice", the Doctor, Amy and Rory are trapped switching back and forth between two realities (one where Amy and Rory are living in a small village expecting a child, and one where they are in the TARDIS) each time they fall asleep (always signalled by the sound of birds singing). Whenever they wake up in one of the realities, they are sure that the other reality was a dream and the current one is the real deal, which is a problem since they encounter mortal dangers in both realities and time continues to pass in a reality where they are asleep (and helpless). They are challenged to figure out which reality is the dream, where they can "safely" die. It turns out both realities were a dream.
- In the Christmas special "Last Christmas", the Doctor and Clara arrive in an arctic research station where the crew seem to have trouble reminding how they came to be there. The Doctor eventually figures out that this is because they are all (including Clara and himself) trapped into a Shared Dream caused by some crab creatures that are sucking their brains out in the real world.
- Encantadia: Sang'gre (Blue Blood Fairy) women can conceive offsprings by holding hands in dreams, sometimes deliberately with a Love Interest or a Chosen Conception Partner, but they can also be guided by the Powers That Be to conceive with a man they never knew before in reality. The sign of the conception's success is a flower appearing out of nowhere on the Sang'gre woman's palm when she wakes up.
- Falling Water: The premise is that a handful of people have the ability to enter other people's dreams. By sleeping next to each other, two or more such people can create a shared dream.
- Glee: This happens to Brittany and Santana when they are put under anesthesia at the dentist together. They both dream of dancing to "Me Against the Music". They note how odd this is when discussing the dream with their friends. This seems to foreshadow their eventual relationship.
- House of Anubis:
- Nina, Fabian, and Amber all receive an ominous dream about an upcoming dance, which ends with Senkhara pushing Nina into the tunnels' chasm. They all discover the next morning that the dream was a shared experience, and soon learn that everything in the dream is coming true.
- Senkhara's Dream Weaver abilities allow her to trap people in very realistic dreams. These dreams often wind up being a shared experience for all the people within it, and they all wake up at the exact same time once the dream is over. One example is when she came to seek the Osirian, appearing to Fabian in a dream. Eddie wound up with the same dream, because he can see ghosts as a natural Osirian ability, but Fabian denied having a dream once they both woke up.
- Star Trek: Voyager: In "Waking Moments", aliens trap the crew in a "collective unconscious" where they dream that their ship has been taken over.
- Fraggle Rock: Fraggles can share one another's dreams. All they need to do is have their heads touching and say, "Dream a dream and see / What a dream can be." Then, when they fall asleep, they can enter one dream. There's even a whole song dedicated to the ritual: "Dream a Dream (and See)."
- The Bible: In Matthew 2:1-12, the Magi (or "wise men") are three distinguished men who have travelled from afar to visit the infant Jesus. Before they reach Bethlehem, they visit King Herod, who asks them to tell him the baby's whereabouts. However, after paying tribute to the infant Jesus, all three Magi are warned in a dream that Herod intends to find and kill the baby, so they return to their homes via a different route, telling Herod nothing.
- Angels in America has a mutual dream scene between the characters of Prior Walter and Harper Pitt, who have never even met in waking life. In the notes preceding the scene in the published script, playwright Tony Kushner admits, "it is bizarre."
- In Dragon Quest XI, after the halfway point of the game, everyone who sleeps in the Warrior's Rest Inn has the same dream of a man in armor calling out. It's turned the inn into quite the tourist attraction. After defeating the Gloomnivore and allowing the man, who turns out to be the Luminary's father, to rest in peace, the dreams stop.
- In Farnham Fables, Ethrea the Dreamgiver is able to create a dream-link between people, bringing them into another person's dream. In Episode 4, she uses this ability to bring Andrew into Theresa's dream, in order to put an end to Althea the Nightmare's mischief.
- In Fate/Grand Order, the protagonist often shares dreams with their Servants due to the nature of their contract. Oftentimes, this involves pulling them into a dreamscape where they confront the less savory parts of their Servants' personalities buried deep within their psyches. Other times these dreams can become muddled with reality as a result of an outside antagonist, such as the protagonist's meeting with Katsushika Hokusai.
- Knights of the Old Republic: A key plot point when it comes to the Player Character and Bastila, who are sharing dreams through Force Bond. They are dreaming of the travels of Revan and Malak as they searched for the Star Forge. Turns out to be even more ominous than even "mere" Force visions They're actually flashbacks the Player Character is having to their forgotten life as Revan.
- Sleepless Domain: On the night she awakens her powers, every Magical Girl experiences what is known as "the Dream". The details of the Dream in question vary for each girl, but they generally seem to feature motifs that reflect the girl's personality and the power she receives. The one consistent element, however, is the appearance of a mysterious woman dressed in an Ethereal White Dress, whom none of the girls can remember after waking.
- At one point in the Arthur episode "Francine Frensky, Olympic Rider", Francine has a dream wherein she is a professional horseback rider in the Olympics, only for her older sister to suddenly show up. "Hey, this is my dream!" Francine says. "Not anymore!" Catherine says, proceeding to show up Francine spectacularly in every way. We then ripple away to show Francine now visibly frustrated and tossing and turning in her sleep while Catherine has a pleasant smile.
- Cow and Chicken: One episode has Mom and Dad waking up from a nightmare where disciplining their children has Gone Horribly Right. They discuss the dream between themselves and lampshade they "must have had one of those shared dreams".
- DuckTales (2017): "A Nightmare on Killmotor Hill!" has Lena's magic accidentally connect all the kids dreams together during a sleepover. They mostly use the experience to have fun, but it also gives them a chance to help Lena deal with recurring nightmares she's been having.
- My Little Pony: Friendship Is Magic:
- Exploited in "Do Princesses Dream of Magic Sheep", where the main characters are hunting the Tantabus, a nightmare-creating creature that infests dreams and, when its host dreams of someone else, becomes able to enter that person's dreams as well. At first, Princess Luna tries to chase it between individual dreams, but when Pinkie dreams about sharing ice cream with everyone else in Ponyville this no longer becomes a viable option. Instead, Luna decides to use her magic to make everyone in Ponyville share a single, collective lucid dream, in which the Tantabus would then be forced to manifest. The result is a nighttime version of Ponyville hosting the dreaming forms of all of its citizens, each independently aware and able to modify themselves and their environment.
- In the Cold Open of "Uprooted", the Tree of Harmony calls the Young Six to Ponyville by bringing them into a collective dream.
- The Powerpuff Girls: In "Power-Noia", the Girls are given nightmares by HIM until they escape their individual dreams and team up in a shared dream to take HIM on.
- Rugrats: "Sweet Dreams" begins with the babies sleeping in Tommy's bed and having dreams. Phil and Lil are revealed to be sharing a dream, wherein Phil rides a frog while Lil rides a flying mud pie. When the twins awaken the next morning, they tell their dream to Tommy, Chuckie, and Kimi, then argue over whose dream was better.
- The Simpsons: Defied in "Who shot Mister Burns? (Part Two)": Chief Wiggum, tasked to find the person who seemingly attempted to murder Mister Burns in the previous episode, is out of clues until he falls asleep and dreams a surreal dream in which Lisa Simpson tells him that he should look at Burns' suit. As Wiggum wakes up, he is approached by fellow policeman Eddie who suggests that they should check Burns' suit for clues. Wiggum asks him in return whether he had "the same backwards-talking dream with the flaming cards", to which Eddie replies with an irritated look and the words "I'll drive".
- Teenage Mutant Ninja Turtles (1987): The events of "Shredderville", which revolved around the turtles visiting an Alternate Universe where Shredder rules the world, are revealed in the end to be a dream the Turtles were all having.
- W.I.T.C.H.: In "E is for Enemy", Nerissa uses her Dream Weaver abilities to try and kill the Guardians in their dreams, which would harm them in real life. As an apparent side effect of this, the girls find that when they're asleep in the same room, they end up in the same dream world. They take advantage of this by having a sleepover, thus enabling them to all be in the same dream at the same time, and fight Nerissa's attack together.