All the light sources are either broken, out of energy, out of fuel (includes wax) or simply not there. The scene is illuminated by a single light. This can be a flashlight or electric lantern, but is usually a lighter, a candle or a matchstick. And yet, despite the tiny size and almost insignificant lumen output of the thing, everything looks as if the light was powered by a nuclear reaction. Rooms, even quite large ones, will be lit up to almost daylight level.
If the light source isn't infinite and the matchstick is depleted, or the battery/fuel runs out, the light extinguishes and everything is suddenly pitch black. Cue the monsters, traps or sentimental/sexual plot twist.
Compare Absurdly Bright Light. Also see Hollywood Darkness, where the ostensible light source is either natural or completely inexplicable... And usually blue. Often appears in the same context as (and immediately after) By the Lights of Their Eyes it wouldn't be much of a Reveal if a darkness-shrouded monster stayed darkness-shrouded after the candle was lit.
Contrast Chiaroscuro, where everything looks like it was actually lit by a real candle.
- In the Panty & Stocking with Garterbelt episode "Once Upon a Time in Garterbelt", Stocking strikes a match and instantly illuminates the entire trap-filled catacomb that lies before them. As they dodge trap after trap, eventually the match burns out and the room goes instantly dark again.
- In Die Hard, the main character is advancing in a ventilation shaft, illuminating his way with a Zippo. The light provided is, however, more akin to a searchlight than to a small flame.
- The Painted Hills: When Taylor and Tommy enter the darkened cabin where Jonathan is laid up with a fever, Taylor strikes a match that illuminates the entire room. This does not pass unremarked on the MST3K version.
- In Scary Movie 2, when Cindy shows Buddy the secret study, he lights one candle, which then illuminates nearly the whole room. As this is a parody film, this is likely intentional.
- In What a Carve Up!, Ernie strikes a match that provides enough illumination to light up the whole secret tunnel. Immediately subverted when he falls down a hole in the floor he somehow failed to notice.
- Subtly parodied in Young Frankenstein, when Frau Blücher (WHINNY!) warns the other characters to "stay close to the candles" she is carrying, because the staircase can be treacherous. None of the candles are even lit.
- An episode of the Jennifer Ehle/Colin Firth Pride and Prejudice (set in 1810-ish) has the Bennetts sit down for dinner. The room is brightly lit as if by sunlight, but behind Mr Bennett you can see it's pitch black outside. There's no way candles or oil lamps could produce such perfect light.
- An episode of Friends does this. There is a blackout, and the friends are bringing in candles for light. Later on, all the candles but one are extinguished, and yet the light level is almost the same. One of the characters then blows on this last candle extinguishing it, and everything goes dark. A sentimental plot twist follows.
- An episode of Little House on the Prairie does this very badly. One of the girls is kidnapped and trapped in a pitch-black cellar... when her captor checks on her while holding a small candle, it's suddenly as if a spotlight was shining down.
- Lampshaded in the Painted Hills episode of Mystery Science Theater 3000.
Tom Servo: That match sure lit up the room!
- In the Supernatural episode "What Is and What Should Never Be" (S02, Ep20), Dean's flashlight is the only light source in an abandoned warehouse on a rainy night.
- In Rosencrantz and Guildenstern Are Dead, the second act opens in near-darkness. Then Hamlet lights a single oil-lamp, and the stagelights all come on. The stage directions even note that this is highly unrealistic.
- Any ostensible light sources on stage are controlled by the lighting technician whenever possible, so an actor "turning on a lamp" will usually just reach up inside the shade to cue the tech to turn on the visible lamp as well as the (much brighter) stage lighting so that it appears turning on the lamp lit up the stage. Where the tech cannot control the on-stage source (a candle or torch), the staging will include a similar obvious cue for the tech to bring up the lights simultaneously. You really can't expect an audience whose eyes have gotten adapted to 10 kilowatts or so of lighting (and that's actually pretty minimal) to adjust to the light given off by a candle in any sort of reasonable time frame.
A 100-watt bulb seems pretty bright in your living room. The average spot on a theatre stage is probably being hit by at least three 500 watt (or more: 575, 750, and 1000 are also common wattages) instruments, focused to direct their entire output into a fairly narrow cone. You can usually still tell a "practical" fixture (an onstage lamp) is on by looking directly at it, but if you look closely you'll notice it doesn't seem to cast any noticeable shadows.
- The Legend of Zelda:
- Zelda II: The Adventure of Link. If you don't have a candle, you cannot see any enemies in dark rooms, even if they are inches in front of you. Once you get the candle, they're visible even if Link and the enemy are on opposite sides of the screen. Note that orange Daira and orange Lizalfos enemies are an exception to the "invisible in dark rooms" rule (the player wasn't expected to run into them before finding the candle, so their palette was not changed for darkened areas).
- The original The Legend of Zelda's Candle items light up dark rooms by tossing a single fireball that burns for only a few seconds.
- When Link lights up a sconce in The Legend of Zelda: A Link to the Past, the whole room lights up. The only difference between how many sconces are lit is how dim or bright the ambient light is.
- The lamp in Link: The Faces of Evil and Zelda: The Wand of Gamelon works similar to the candle in Zelda II. One use of the lantern lights up the entire dark area for a limited time, and requires lantern oil.
- Pokémon's Flash ability used to do this, lighting up dark caves entirely (what made some caves pitch-black and others not was never explained). In the newer games, though, it's just an expanded circle of light around the player.
- All three games in the Serpent Riders trilogy (Heretic, Hexen and Hexen II) have torches as consumable items. In the first two games, they light up the entire map with a fire-like flickering effect, while in Hexen II, it lights up a large circle around the player. In both cases, it burns out after a while.
- Doom has the Light Amplification Visor. Its gimmick is simple: turn the brightness of all map sectors to max (known as "fullbright") for two minutes. According to the press release beta, the LAV was meant to work like a set of Night-Vision Goggles by applying a green colormap to the screen, but because the visual engine was limited and the sprites were difficult to discern, this idea was abandoned, although the GZDoom source port brings this back (with some improvements like highlighted monster and item sprites a la Duke Nukem) as a native option.
- In the NES version of Bionic Commando, the Flares illuminate the entire screen in the otherwise pitch dark Area 4. In Rearmed, they instead have a Chiaroscuro effect.
- Anglerfish lures usually are little more than a faint dot in an ocean of darkness. Yet in Feeding Frenzy: Shipwreck Showdown's Blackout Basement levels, Edie's esca can illuminate a sizeable area around it, and even the entire screen.