So you've got a villain shooting at you with his Ray Gun. You really don't want to get hit by it, and you know his A-Team Firing won't last forever... so what do you do? You take out your mirror and use it as a shield, and surprise, it reflects the ray right back at him.
Why does it work? Because in fiction, Mirrors Reflect Everything (except perhaps a vampire's image, but that's another trope).
This trope is when something that even remotely resembles a beam of light can be deflected using a mirror (and not a Magic Mirror, either, just an ordinary mirror), even though it realistically shouldn't have even stopped it. Or if you don't have a mirror handy, you can substitute anything reflective. Whatever was fired at you will always be deflected, perfectly, without any distortion or loss of potency.
Note: only non-justified examples belong here. If it's something that would make perfect sense for a mirror to reflect, like simple laser-light, or if the mirror is explicitly enchanted in a way that allows it to reflect such attacks, it doesn't count. This restriction is necessary to keep the trope out of chair territory.
- Parodied in Ayakashi Triangle: When Medusa attacks Lu's manor, she knows the "standard" tactic for such an enemy is to reflects its powers back at it with a giant mirror. We don't see if it works because Medusa can also see through the eyes of her snakes, keeping her main eyes closed while immediately smashing the mirror to pieces.
- In Gundam Build Fighters: GM's Counterattack, one of the villains within the Gunpla Mafia uses a Bound Doc covered in "diamond coating", which makes it strong enough to reflect even the most powerful beam attacks. Unfortunately, it doesn't protect from attacks from the bottom, which Ricardo Felini uses to great effect.
- In Mobile Suit Gundam SEED Destiny, the Akatsuki Gundam is covered in a golden mirror coating called Yata-no-Kagami that reflects ALL beam attacks. And in a time where virtually every mobile suit is using a beam weapon, this makes it extremely powerful.
- In Pokémon: The Series, mirrors have been used to reflect hypnosis waves. The reason this happens is... never explained. It just does.
- Rebuild World: Sometimes mirrors are used to reflect Energy Weapon attacks, like a giant bee Mechanical Monster being a Drone Deployer of drones with mirrors to redirect its Beam Spam, or the Super-Soldier Haruka using mirrors to shoot her energy weapons around corners.
- An early episode of Sailor Moon pits her against a photography-themed Monster of the Week who traps people in the pictures it takes. She defeats it by standing in front of a mirror, then dodging the photo beam, causing it to reflect right back at the youma.
- In YuYu Hakusho, Yusuke defeats Hiei by bouncing his Spirit Gun off a mirror, since Hiei was fast enough to dodge a direct attack. The mirror in question was actually the Forlorn Hope, which is magic but was never stated to have any attack deflecting power, and was broken in the process. In fact, the villain who had the mirror in his possession asked how Yusuke knew the attack would reflect and it turns out he just guessed.
- In the first arc of the Buffy the Vampire Slayer Season 8 comics, the Scoobies open a portal to the military base Willow's being held captive. The villains have some kind of laser BFG waiting for them, and open fire the second the portal opens - except the Scoobies saw that coming and have a giant mirror ready.
Xander: Magic. It's all done with mirrors.
- In Dirty Pair: Dangerous Acquaintances, the bad guys have programmed a spaceship's security system to seal off areas of the interior by lowering raisable walls and to use laser turrets to shoot anything that moves within those areas. The main characters retreat into a bathroom where there are no turrets, then break the mirror and use pieces of it to redirect the turrets' laser beams, first to cut through the nearest raisable wall, and then to destroy the turrets. In issue 3 of the next miniseries (A Plague of Angels), the letter column ran one letter from someone who pointed out that a high-powered laser actually would have quickly made a hole in the mirror.
- In The Further Adventures of Indiana Jones #8, Indy uses Marion's compact to reflect the laser beam generated by a Solar-Powered Magnifying Glass into the door of their cell: weakening it enough to allow him to break it down.
- In Soulsearchers and Company #1, Kelly hoists a mirror in front of Evil Sorcerer Grand Guignol as he is attempting to cast a spell on her stuffed toys. The spell bounces off and turns Guignol into a stuffed toy.
- Superman exploits this effect in the comic books. In one series, he uses it to shave. After all, steel razor blades aren't gonna do the trick, are they? Then his powers get swapped for electrically based ones that he has poor control over. The next morning, he tries it again. Lois has just enough time to catch on to what's about to happen before Clark lets it rip. This is also reflected, blasting Clark through the whole apartment, trailing lightning bolts all the way.
- Dungeon Keeper Ami: Azzathra's anti-magic gaze can be enhanced if his users look through mirrored orbs, since those mirrors can reflect the gaze onto new areas.
- In All Mixed Up!, Otto's handheld compact mirror is able to reflect the beam from Mariana Mag's lifeline directly back at her with accurate precision, enough to turn her into her own personalized anagrammed object.
- Its Dangerous To Guard Alone: Brave Heart's shield, which given how he's a reference to Link from The Legend of Zelda, might be the Mirror Shield, can reflect spells:
Starlight glowered and fired off another few shots, which proceeded to bounce off of the shield's polished surface, making her scramble out of the way.
- In an early draft of the opening for The Incredibles, Mr. Incredible uses a mirror to reflect Syndrome's stasis beam back at him.
- Shrek 2: Towards the end of the film, when Fairy Godmother fires a spell at the Human Shrek, King Harold dives in the way and uses his armor to rebound the spell back to its sender, which does disintegrate her into bubbles. However, it does not protect Harold against the magic though. It turns him into a frog, his actual true form.
- The Magic Door: When the Black Witch shoots a spell towards Sally, Liam uses a mirror to deflect the spell back at her. He explains how by saying "Simple physics".
- Taken to the extreme in the climax of the Malaysian epic, The Malay Chronicles: Bloodlines. Facing an army of pirates which outnumbers them a dozen to one, the hero devises an ancient weapon, the Archimedes Heat Ray, which is created by breaking up several mirrors and sticking them on various panels, spread out in the shape of several petals. By having sunlight reflected off from one surface to another, and magnifying the beams multiple times, allows the heroes to create an impromptu laser blaster (in the 16th century!) which incinerates and wipes out a quarter of the pirate army within a few minutes.
- Spaceballs: Lone Starr uses a shaving mirror to deflect the Agony Beam Dark Helmet shoots at him.
- In Superman II, General Zod has heat vision powerful enough to melt steel and scorch concrete. Nevertheless, Superman is able to use a semi-truck's side mirror to reflect the heat vision back at the villain. Subverted in Superman III, where a drunken Superman who can't stand to see his own face melts the mirrors in a bar.
- Tenacious D in The Pick of Destiny, when Satan fires lighting at Kage, Jables dives in front of him in an attempt to take the bullet. By pure dumb luck, the lightning hits the shiny foil "JB" logo that Jables had stuck onto his guitar, which reflects it back at Satan and breaks a piece off one of his horns, allowing Tenacious D to perform the spell that sealed him away the first time.
- Ultraman Cosmos: The First Contact has the titular Ultra losing his energy after an epic battle against Dark Baltan, where he encounters his future host, Haruno Musashi, who is then still a child on a camping trip. Musashi realize Cosmos' energy can be restored by directing sunlight into his Colour Timer, and so uses aluminum foils, metal cups, ladles and spoons to reflect the sunlight into Cosmos' Timer. It works.
- In Watchmen, Ozymandias uses a pot lid to reflect a shot from an energy weapon fired by Nite Owl II.
- The Ghosts of Fear Street book Three Evil Wishes ends with the villainous genie trying to trap the protagonists in his bottle, only for his spell to hit a mirror and suck him back inside instead.
- In the first story of Sideways Stories from Wayside School, Mrs. Gorf threatens to turn all the kids back into apples. Jenny thinks fast and holds up a mirror, which deflects the spell and turns Mrs. Gorf into an apple.
- Done in an early episode of Buffy the Vampire Slayer, where Buffy uses a lab mirror to reflect a witch's magic attack. This traps the witch in her own cheerleading trophy.
- Doctor Who:
- "The Face of Evil": The Doctor uses a hand mirror to reflect the Teshes' particle analyzer.
- "Robot of Sherwood": The Doctor and the peasant slaves uses gold plates to reflect the lasers of the robot knights back upon the knights.
- "Spyfall": Faced with an attempted Murder by Remote Control Vehicle involving a deadly disintegrator beam that killed the driver and is firing at the others in the car, the Doctor rips off the rear-view mirror of the SUV she and her companions are in to deflect the beam back into the hacked computer, destroying it.
- The Flash (1990): Flash defeats Captain Cold by reflecting his cold beam back at him.
- In The Green Hornet episode "Invasion from Outer Space" part 2, the title character reflects a blast of electricity with a mirror.
- In one episode of the children's TV show Jigsaw, the villain of the week had a ray gun that would capture characters in TV sets. Until he tried it on the Double O men, one of whom (Sylvester McCoy) was engaging in Obfuscating Stupidity by admiring his reflection in a hand mirror.
- Odd Squad: In "Perfect Score", Olympia uses her mirror suit to reflect Freeze Ray Ray's freeze ray back at him; freezing him inside a block of ice.
- Power Rangers Wild Force: After Jindrax goes Defector from Decadence and rails against how his superiors will betray their own kind to get what they want, Onikage proves him right by using his "evil-shadow-maker" attack on him. Jindrax deflects it with his mirror, which ends up saving the Rangers.
- One episode of Star Trek: Voyager had a Viidian ship hide in an asteroid full of natural mirrors which reflected phaser fire (which are not lasers, but some kind of particle weapon). The crew got around this by setting the phasers to a low setting and firing a continuous burst, hitting but not damaging the other ship to reveal its location.
- Depeding on which version you read, either the hideous visage of Medusa had no effect on Perseus because he only looked at her reflection in a mirror, or the mirror turned Medusa herself into stone by reflecting her image back at her. This may make sense because originally what made her so lethal to be around wasn't some kind of Deadly Gaze but her sheer hideousness, which is of course something a mirror can reflect.
- Whether or not this trope applies to gaze weapons, and to which particular gaze weapons, was the subject of a lot of frustrating debates in the early days of Dungeons & Dragons, when monsters' descriptions didn't offer many technical details about how their attacks worked.
- Rifts has a Magitek mirror shield that can reflect attacks, but this is primarily because it incorporates a spell designed for just that effect. Given the mildly psychosomatic nature of Techno-Wizardry, the mirroring is likely done to invoke the trope to help the spell chains stick.
- In a Aladdin Edutainment computer game, one of the last activities is to set up a specific arrangement of treasures in the Cave of Wonders. This turns out to allow the ruby given to your party earlier to reflect Jafar's spell, trapping him again in the same vault he was released from in the beginning of the game.
- The ClueFinders Reading Adventures Ages 9–12: Mystery of the Missing Amulet uses this as a Chekhov's Gun. During the opening cutscene, Owen is using LapTrap's shell as a mirror to comb his hair, which LapTrap resents. At the end of the game, Owen once again uses LapTrap's shiny shell as a mirror to reflect the eponymous amulet's powers back at the evil sorceress Malicia, trapping her inside the amulet.
- Used in Day of the Tentacle when the protagonists convince Purple Tentacle to use his shrink ray on Dr. Fred. The ray reflects off Dr. Fred's surgeon's head mirror, shrinking Purple Tentacle to the size of a worm.
- This trope is an instrumental player in the finale of the adventure game Flight of the Amazon Queen: Joe has to set up a chain of deflections for Ironstein's dino ray gun involving Faye's hand mirror, a reflective ceremonial death mask and the guardian robot's crystalline body.
- Exaggerated with Mirror Copy Ability in Kirby. The objects it can reflect include, but not limited to, lasers, icicles, cutters, sword beams, fireballs, gusts of wind, feathers…
- In the first The Legend of Kyrandia game, you defeat the Big Bad by having a mirror reflect magic back at him.
- The Legend of Zelda has a recurring item in the Mirror Shield, pictured above. In addition to the typical applications (at least in the 3D installments; the 2D games usually just treat it as an upgraded shield), Ocarina of Time has you use it to defeat one Dual Boss by reflecting one sister's magical attack at the other, then absorbing three like beams in a row and spewing the whole charge at the combined sisters in the second phase. And in The Wind Waker, it can reflect freakin' Light Arrows in the final boss fight. You can also reflect Wizzrobe's fire and ice attacks back at him in Majora's Mask, just because in Ocarina of Time (its immediate predecessor) it was used to reflect heat and cold attacks. In the remake of Link's Awakening, every kind of projectile attack bounces back and strikes the enemy that launched it, even rocks and spears, with nothing to suggest that the shield is supposed to have any magical properties.
- The first Quest for Glory does this, but it's justified since the mirror is explicitly described as having an enchantment on it that reflects magic.
- Shantae: The Mirror variant of the Bubble Shield:
- In the climactic scene of Space Ace, Borf fires his Infanto Ray at Ace, who moves a mirror into place and reflects it back at him. The Infanto Ray isn't a laser, it's a beam that turns its target into a baby.
- In the French webfiction Les Aventures de Morgoth, the protagonist uses a mirror with an invisibility spell on it to reflect an unsuspecting monster's petrifying gaze. It is lampshaded beforehand with a line the likes of "I know it shouldn't work, but it has been proven it works anyway." It does, but the target shrugs if off quickly.
- The New Kids on the Rock Christmas special, Ryan's Christmas Wish, Neil Cicierega uses a mirror to reflect the Misery Meister's ultimate attack: a bullet from a mundane revolver.
- All Hail King Julien:
- In what can only be a Visual Pun, in "Exiled" Mort attempts to assassinate Koto with a crossbow, but when his bolt misses and hits a mirror instead, it reflects off and hits him instead.
- Later on, suspecting Karl's final plan would likely involve some kind of doomsday laser, Julien has his citizens bring poster boards to cheer him on with that are backed with mirrors, so that when Karl does fire his laser, they can all hold their mirrors up and reflect the laser away.
- In Batman Beyond episode 13 ("Ascension") Blight fires a small blast of flame-like radiation and Batman reflects it back at him with a metal serving tray. The impact does blow Batman across the room and destroy the tray, but the blast indeed bounces back at Blight.
- Code Lyoko: In the episode "Music Soothes the Savage Beast", a mirror is used to send back the electrical attacks of XANA's specters. This happens in the real world, not in a the virtual world where it could be hand-waved.
- In Home: Adventures with Tip & Oh, when playing a video game Lords n Lasers, Shapeshifter Oh finds himself cornered by K-Trong who has acquired the game's Infinity +1 Sword, the Laser Sword. Thinking fast, Oh shape shifts into a Disco Ball, and when K-Trong tries to cut it, the sword instead refracts off of the disco ball, cutting K-Trong into pieces.
- Jonny Quest episode "Mystery of the Lizard Men". The Big Bad has a laser powerful enough to instantly blow up entire ships. Dr. Quest uses an ordinary mirror to reflect the beam and blow up the Big Bad's ship.
- In Justice League episode 14 ("The Fury") Batman uses a conveniently placed mirror to reflect the force beams from Star Sapphire's crystal right back at her.
- Kim Possible has done this many times with her compact mirror.
- In the Sushi Pack episode "Pants On Fire," The Pack use a mirror to reflect a bolt of lightning shot by Unagi.
- Xiaolin Showdown: One of the abilities of the Reversing Mirror is to reflect the powers of other Shen Gong Wu towards the opponent. It mainly however is used to cause other Shen Gong Wu to do the opposite of their normal function. In one scene where Jack Spicer shrinks down and goes inside of somebody's brain, he uses the Reversing Mirror as a shield against the electrical sparks in the brain.