[...] how was a girl from Earth to fully understand?
h amount of fuel will not power an EDS with a mass of m plus x safely to its destination. To him and her brother and parents she was a sweet-faced girl in her teens; to the laws of nature she was x, the unwanted factor in a cold equation.
A spaceship has been damaged and is Almost Out of Oxygen
(or food or fuel). But then someone calculates that if they had one fewer
crewmember, they just might make it back safely...
Can also apply to circumstances outside of Science Fiction
. Such incidents have even happened in real life, involving sailors in lifeboats running out of food or freeboard
. These seldom involved any fine calculations, just desperate people willing to do anything to live a bit longer. Those who travel on spaceships are presumed to be a different breed, or perhaps they're just more educated; therefore expect a Lottery Of Doom
, Drawing Straws
or Heroic Sacrifice
See also Emergency Cargo Dump
, No Party Like a Donner Party
and Cut the Safety Rope
. A subtrope of Someone Has to Die
Note: Please do not include
discussions on the short story The Cold Equations
here. Post them on the discussion page for that story.
As a Death Trope, all Spoilers will be unmarked ahead. Beware.
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- Played for laughs in a Super Bowl Special commercial, where an airplane which has crahsed on a Desert Island can take off but only if they lighten the load. They have to leave behind the cases and cases of tasty beer cargo. But they manage to Take a Third Option by removing the plane's fuselage, so now the beer can come with them.
Anime & Manga
- In the second season of Vandread, The Stoic Meia has to take care of Ezra's baby daughter when a space battle breaks out and in the confusion, they accidentally launch in an escape pod. When oxygen begins to run out, Meia has no choice but to throw herself out of the airlock (with a smile, no less) to make sure Karu lasts until the pod is picked up by Nirvana. It turns out, the pod has just been picked up, and Meia didn't notice until she walked out.
- Lampshaded in the Martian Successor Nadesico episode "The Lukewarm 'Cold Equation'", where Anti-Hero Akito gets stranded without fuel after piloting his Humongous Mecha out of range of the Cool Starship, and the two leading contenders in the Love Dodecahedron get stranded with him when their rescue attempts fail due to enemy attacks. Akito ejects the mecha's limbs to get it moving, but the oxygen issue comes up again. Akito finally decides to Take a Third Option before they discover that they'd drifted back in range of their starship.
- The reason for a series of murders in The Kindaichi Case Files. The victims are all survivors of a crashed ship, with the same initials. One of them had worked out this equation and pushed a girl off who was trying to climb aboard a full lifeboat; in falling, she managed to grab their keychain with their initials.
- It is alleged that Godwin (author of "The Cold Equations") essentially took the story from a story published in EC Comics' Weird Science #13, May-June 1952, called "A Weighty Decision," scripted by Al Feldstein. In that story there are three astronauts who are intended to be on the flight, not one, and the additional passenger, a girl that one of the astronauts has fallen in love with, is trapped aboard by a mistake rather than stowing away. As in The Cold Equations, various measures are proposed but the only one which will not lead to worse disaster is for the unwitting passenger to be jettisoned. Other sources note that the theme of Feldstein's story is itself strikingly similarly to the story "Precedent", published by E.C. Tubb in 1949; in that story, as in the others, a stowaway must be ejected from a spaceship because the fuel aboard is only enough for the planned passengers. These sources argue that neither Feldstein nor Godwin intentionally "swiped" from the stories that came before, but merely produced similar variations on an ancient theme, that of an individual being sacrificed so that the rest may survive.
- In the Tintin comic album Explorers on the Moon, when Thompson and Thomson turn up as stowaways on the Moon-Rocket, Calculus worries that, since oxygen supplies were assessed for only four people, there might not be enough for six, and decides to shorten the trip from fourteen to ten days. It gets worse when Colonel Jorgen is revealed to have smuggled himself on board, with the help of The Mole. He intends to maroon Tintin and his companions on the surface of the Moon, pointing out that they don't have enough oxygen to bring prisoners back to Earth. Later when the villains are overpowered, Tintin refuses to leave them behind despite having exactly the same problem. After Jorgen is killed in a Gun Struggle, Wolff decides to atone for his actions by stepping out the airlock. Even so Tintin and his companions almost don't make it back to Earth.
- Rick Random: Space Detective, a comic of the 1950's. In "Kidnappers from Mars!" Space Pirates get their vessel caught in a 'space tide' and realise the only means of escape is the two-man space shuttle. The Big Bad and his Femme Fatale girlfriend hide until all the other pirates have killed each other fighting over the shuttle, then take off in it.
- Twisted for a Xxxenophile story. The bomb shelter will only hold two, and the female character tells her two male companions that if she has to repopulate the Earth she wants to enjoy herself doing it, so "auditions" are now in order. World War III did not just break out, she said it had as an excuse for threesome sex.
- Echoed and possibly referenced by Mark Verheiden and Mark A. Nelson's follow-on graphic novel set ten years after Aliens. Hicks smuggles Newt aboard a weight-critical ("gravity-balanced") ship on its way to the alien homeworld. The situation is averted on this occasion, as he took pains to dump stores equivalent to her weight before takeoff.
- Woman in the Moon (1929). After a struggle punctures the oxygen tank, the two male crewmembers draw straws to see who gets to return to Earth on the rocket. The Dirty Coward gets the short straw and breaks down sobbing, so the hero makes the Heroic Sacrifice and stays behind on the Moon instead.
- Destination Moon (1950). The rocketship loses reaction mass landing on the moon, so someone has to stay behind even after they've thrown out every piece of equipment they can unbolt. While the Science Heroes are arguing over who gets to make the Heroic Sacrifice, the Plucky Comic Relief sneaks outside and laconically tells the others to take off without him. Fortunately someone realises how to dispose of an extra piece of equipment so they can all return safely.
- Alien (1979). After the xenomorph does some snacking, there are four crew members left.
Lambert: "I say that we abandon this ship. We get the shuttle and just get the hell out of here; we take our chances and hope that somebody picks us up!"
Ripley: "Lambert, the shuttle won't take four."
Parker: "I'm not drawing any straws. I'm for killing that goddamned thing right now."
- Starflight One (1983). Disaster movie involving a hypersonic passenger plane that gets stuck in orbit. Most of the passengers are successfully evacuated and the crew intends to try and achieve reentry, but they're running out of oxygen (the plane is only meant to pass through space for a short time before returning to Earth). A Corrupt Corporate Executive on the ground half-heartedly suggests that if there were three less passengers... The pilot demands this jerk be thrown out of the control room, and he is.
- Lifepod (1993), set in an escape pod ejected from a sabotaged spaceship with limited air, food and water. Stating that their odds of survival would increase if one of them dies, a blind passenger tries to cut his wrists. He's actually the saboteur, and did it knowing the others would stop him.
- Sunshine (2007).
- Icarus II is damaged on its mission to reignite the sun, but the crew realise they can still get there if one of them dies. A scientist who's lapsed into depression after indirectly causing the death of The Captain (and soon the rest of them even more indirectly) is an obvious candidate. All but one of the crew vote to kill him (their mission is, after all, to save the entire human race) only to find he's already killed himself. Or he was killed by a stowaway whose presence makes the whole question moot.
- When there's only one spacesuit to cross back to the Icarus — the other crewmen immediately start putting Capa (the only man who can fire the bomb) into the suit, ignoring the protests of their commander.
- Marooned (1969 — made before the Apollo 13 disaster). The crew of an Apollo mission is left stranded in Earth orbit with no means to deorbit and a dwindling oxygen supply. Both an emergency rescue mission and a passing cosmonaut eventually help the crew, but not before the mission's commander decides to sacrifice himself.
- This is evoked at one point in Red Planet, and one of the three still-alive crewmen decides to try and reach the old Russian module alone. The second crewman later dies protecting the third one.
- The Transporter has one in the opening sequence. Frank is hired to be the wheel man for a bank robbery, with the express and very clear agreement that there will be three men at 254 kilos. The gang shows up with four men. Frank refuses to budge, since he has planned for a very precise amount of fuel to optimally carry three men plus himself and not one smidgen more. The gang's left with the choice of kicking out one man to make weight or sitting still and waiting to be caught. There's nothing tying Frank to the gang, so he's perfectly willing to cool his heels. Finally, the gang leader shoots one of the accomplices and throws his body out, at which point Frank springs into action and proves himself and his ways worth every penny.
- In Titanic, this is the reason given why the lifeboats don't go back to try to save those in the water after the Titanic sinks: if they go, they'll be mobbed by people trying to get on the boat, causing the lifeboats to sink and killing the passengers aboard them.
- After The Dark is all about debating this trope, when a teacher sets the below-mentioned nuclear bunker scenario to his students.
- In Interstellar, Cooper does a Heroic Sacrifice by detaching himself from the spaceship to ensure Brand's safe onward travel to Edmunds planet. Apparently, resources weren't enough for both of them to survive.
- One of the pub crowd in An American Werewolf in London tells a joke about a plane full of U.N. representatives who need to lighten the load or they'll crash. Just tossing out the baggage and seats isn't enough, so two of the diplomats jump out heroically ... and the third, a Texan, tosses the Mexican diplomat out.
- The Last Days on Mars (2013). Campbell, Irwin, and Rebecca escape the Mars expedition base in the solar-powered land Rover, but as it's night the Rover doesn't have enough power to reach the landing zone where a Drop Ship will pick them up. They could walk the rest of the way, but their infected colleagues are coming after them and Rebecca has been wounded in the leg. She's a suspected Zombie Infectee, so Irwin suggests they leave her behind. Campbell refuses, but then Irwin remembers there's another Rover nearby they can use instead. The Take a Third Option trope is defied however when Irwin steals the Rover after unsuccessfully trying once more to persuade Campbell to abandon Rebecca.
- Five Came Back: A plane has crashed in the jungles of the Amazon. The pilots fix it, but due to one of the engines being damaged beyond repair, the plane can carry only five people. Unfortunately there are ten people in the party, and it's the Cold Equation because the sound of drums has revealed that The Natives Are Restless, and they're headhunters, and they're about to attack.
Live Action TV
- A strange, comedy example from the episode "Real Time" of Workaholics-the guys are still drunk in the morning, and need to stay drunk rather than get hungover before they arrive at work. Adam runs back to get beers for them, but drinks them all himself (along with a few pulls of whiskey). He meets up with the others, tells them all the beers are gone, and we get this exchange.
Ders What are you talking about? I just saw you drink one right now.
Adam: Yeah, the last one Ders. Think, speak.
Blake: Okay, well, I know we had more than one beer in the house.
Adam: - No, we had four. But there's three of us. And 1 1/2 beers each? That's not enough to get us kablamo-ed. But for one person? that might be enough to take us to the level.
- Star Trek: Enterprise ("Shuttlepod One"). Trip Tucker and Malcolm Reed are stranded on a shuttle, and Tucker decides to throw himself out the airlock to give his companion more time, only to be ordered back at phaser-point by Reed.
- Star Trek: The Original Series
- The episode "The Galileo Seven". When the shuttlecraft Galileo crash lands on a planet, it loses so much fuel that it can't even reach stable orbit unless they lighten their load by 500 lbs. It's immediately pointed out that 500 lbs. is the weight of three men. Two of the crew die while on the planet, and they eventually take off and achieve orbit. Unfortunately they had to use the boosters to do so, so they're guaranteed to burn up on re-entry.
- Another Star Trek: TOS episode "The Conscience of the King" had this, not in a space ship but on a planet. Kodos "the Executioner", former governor of the Earth colony of Tarsus IV, was responsible for the massacre of over 4000 people, including members of Kirk's family. Governor Kodos had ordered the executions of more than half Tarsus IV's population after the food supply was all but destroyed by a fungus. This would have allowed the rest of the population to survive until relief came. It so happened that the vital resupply ships that could have saved the whole colony arrived much sooner than Kodos had anticipated, rendering all the executions unnecessary. A large part of his infamy came from the fact that he didn't choose randomly or pragmatically, but based on some eugenics formula he had developed. Made worse in hindsight, when it turned out that Hoshi, who was on the first major expedition by humans into deep space, helped develop the Universal Translator and saved Earth from the Xindi, apparently didn't measure up.
- Star Trek: Voyager
- In "Deadlock" a Negative Space Wedgie creates two Voyager's occupying the same space. One is damaged in the process, so the captain of that Voyager decides to destroy her own ship so the other can survive. But hostile aliens board the other Voyager, so that Captain Janeway ends up destroying her ship instead.
- "One" had the ship traversing a deadly nebula with most of the crew in stasis for their safety. Near the end of the trip, the ship's systems start breaking down, and there isn't enough energy to keep the engines running. Seven of Nine has to choose which systems to divert power from, and hallucinations of the crew mock her for thinking that she could take a few of the stasis pods offline to get the engines running, calling it heartless Borg efficiency. She does so, then takes life support offline to keep the stasis pods running. Luckily for everyone, the ship exits the nebula in time to for the crew to awaken and save her.
- Blake's 7 episode "Orbit". Anti-Hero Avon and Dirty Coward Vila are on a shuttle desperately trying to achieve escape velocity. They throw out everything they can but are short seventy kilos. It turns out that the shuttle is being weighed down by a piece of super-dense matter. Once Avon finds it all he has to do is push it out the airlock - if he can, because it's so damn heavy. Trouble is, he can't get Vila to help him because he's scared Vila into hiding.
Avon: "Not enough, not nearly enough! DAMMIT! What weighs 70 kilos?!"
Orac: "Vila weighs 73 kilos, Avon."
Avon: (pulling out a handgun) "Vila..."
- In one episode of Bones twins had been abducted by The Gravedigger, who buries his victims and demands ransom or they will die in exactly 24 hours (due to suffocation). Except in this case since the Gravedigger didn't expect to abduct two people so they only have 12 hours of air. One was seriously injured and killed himself so the other might be able to hang on a bit longer.
- An episode of Space: Above and Beyond involved a vast ship with a bunch of survival modules, one of which had to be sacrificed for power. The guy has trouble pushing the button, because his younger sister is in the one module that isn't full.
- The lifeboat version is mocked in an episode of Monty Python's Flying Circus.
- Played for Laughs in Red Dwarf. Due to the ship exploding, the crew are stuck in a Starbug shuttle, with limited supplies, and neither enough fuel nor oxygen to get to the nearest planet.
: (to Kryten
) Well, you and I don't use oxygen, do we? So, if we kill [Lister and The Cat] and dump their bodies out the airlock
, will that save us enough fuel to get to safety?
Kryten: The point is moot, sir, as we only have enough battery power [to run your holographic emitter] for two minutes.
- Dad's Army. Captain Mainwaring is presented with this scenario to test his decision-making skills: You are in a balloon over enemy territory that is slowly running out of air; who do you throw out? Mainwaring claims he would normally throw himself out but he realises he is too important for that. He decides on Godfrey, who doesn't look very happy.
- Wilson then suggests they wait till the balloon reaches the ground then Godfrey can step out.
- In LOST's fourth-season finale, as the group of main characters attempts to finally leave the island, Frank notices that the helicopter is running low on fuel, and says they'll have to jettison someone to stay in the air. It initially looks like Hurley will have to jump (judging by his reaction when Frank says this), but Sawyer performs a selfless act by jumping out of the aircraft himself and allowing everyone to escape.
- Subverted in the Stargate SG-1 episode "Tangent". Instead of killing himself, Teal'c places himself in a kel'no'reem trance to reduce his oxygen consumption for O'Neill's benefit.
- In Legend of the Seeker, Cara and Kahlan both realize that the tomb that they're trapped in doesn't have enough air for both of them. They both give reasons that they should die and the other live - Kahlan that Cara could revive her, and Cara that she's less important to Richard, to whom she's sworn. They even briefly fight to prevent the other from committing suicide - and in doing so, use up the last of their air. Seconds later, Richard and Co bust in.
- In "The Joining", an episode of the new Outer Limits, a group of scientists are trapped on Venus with limited life support. When there are only two of them left, one kills himself to prolong the other's life.
- On My Name Is Earl, one of the people on Earl's list happens to be an eccentric old woman (played by Betty White) that the citizens of Camden accused of being a witch. She gleefully traps them in her basement, but she's running out of room, and says she'll have to start killing them. But she's "nice" enough to let them choose who that is. Cue lots of arguing.
- The 100:
- The Ark has only four months of life support left for its current population, so the option is quickly raised to "reduce" the population to buy time to repair it. This is rejected only because the person with the authority to make such a decision refuses to kill hundreds of innocent people without a legal reason.
- All crimes on the Ark are punishable by death in order to save on life support. The only exception is if the convict is under 18.
- Battlestar Galactica (Reimagined). In the webisode series "The Face of the Enemy" Felix Gaeta and a mixed company of humans and Cylons make an emergency jump in their Raptor and (due to a computer error) get stranded far from the fleet. One of the Cylons murders the others (with the exception of Gaeta, her former lover) so they'll have the maximum chance of survival.
- Played for laughs in 30 Rock: Jack wants to prove that Kenneth isn't really as selfless as everyone thinks, so he fakes a setup where nine people are trapped in an elevator, and tells them all that they have only enough air for eight. Kenneth doesn't even hesitate before he pulls off his own belt and tries to choke himself, much to everyone's horror.
- Battletech, in the Wars of Reaving Clans Steel Viper, and Star Adder just obtain a great deal of isorla(spoils of war) from fleeing Clan Snow Raven fleet. When they didn't have enough room for all their isorla, they decided to throw out clan civilians out the air lock.
- In one ending of Ever17, Tsugumi and Takeshi find an escape module with which to leave LeMU, but it turns out not to be able to carry both of them to the surface, so one of them ends up having to sacrifice themselves for the other. In case you were morbidly curious as to who self-sacrifices for whom, Takeshi sacrifices himself so Tsugumi can live.
- Played with in Nine Hours, Nine Persons, Nine Doors, in which the nine characters have nine hours to find their way off of a cruise ship. Along the way, they must solve puzzles behind numbered doors, which only three to five people may enter. They may escape when they make it through a door with a nine on it, and some of the characters realize early on that no more than five people can escape. Later subverted when the doors with the nines are found, and the protagonist contemplates that the purpose of there being two was to inflict regret upon those who sacrificed members after doing the math. However, this is soon double subverted when, after the two doors, there is another room with a single door with a nine; characters who are left behind after that will still have a chance to escape, but they don't know that when deciding who passes through the door.
- In Sands of Destruction, a desperate and depressed Kyrie decides that if Naja kills him, Morte and the others will be able to continue to live because he can't destroy the world if he's dead. An interesting case where this trope meets Heroic Sacrifice.
- The short film "Vacuity" involves a man on a damaged space station who's forced to choose between saving himself by ejecting the escape pod he's in (it's airlock will open in a few minutes and due to the damage suffered, ejecting is the only way to abort the opening) or sacrificing himself so that the rest of the station's crew can cut their way into the escape pod and use it. Complicating matters is the fact that he can't contact the rest of the station, so he has no idea if the rest of the crew is even still alive. Ultimately he decides to let himself die after he manages to hear the other crewmembers trying to get in to help him, feeling that he can't be as selfish as to let others die so he can live.'
- In Swan Song, part of the Roll Play series of Dungeons & Dragons livestreamed shows, this is the core of the plot of the 8th "episode" or week. After a couple of botched jumps on already-low life support by the ship's navigator, the crew math-out that they have significantly fewer person-days of life support than they need for their five-man ship. The doctor of the ship has to put first their escorted passenger, then the rest of the crew bar the navigator, including himself, into a risky experimental coma to preserve the little remaining life support (cutting resource usage into a tenth). Piling on the problem, they are also low on fuel with their method of manual fuel extraction destroyed, so they discuss and realize that their only option is to go to a modern-day-era tech-level system and hope they can refuel on the desolate refueling station until they find a higher-tech system that offers a way to resuscitate the comatose crew... assuming they can even be put into a coma with the combination of space-morphine and dice rolls. Miraculously, they do... but the navigator then realizes that while he made it to the system, he doesn't have the life support to fly to a fuel station and must instead crash-land onto the only inhabited planet.
- In an episode of Futurama, this occurs when the Space Titanic is sinking into a black hole. The main characters board an escape pod, but the extra weight of Bender's Girl of the Week is causing the escape pod to drift towards the black hole, so she willingly lets go, saving the other characters. She is, of course, killed by falling into the black hole, and is never heard from (or even mentioned) again.
- The nuclear shelter scenario is spoofed in The Simpsons episode "Bart's Comet". A comet is about to strike Springfield and so the entire towns' population tries to cram into Ned Flander's bomb shelter. They somehow manage this, but can't get the door closed. After arguing about who should be sacrificed Homer points out that the one skill future society doesn't need is the ability to sell left-handed products, so Ned gets thrown out of his own shelter. Eventually they all feel guilty about this decision, so leave the shelter to die with him. The comet ends up striking the bomb shelter and destroying it.
- This crops up in Transformers: The Movie, with the Decepticons (who are retreating from a battle on Earth back to Cybertron) finding out that there's not enough fuel to make the voyage with the current amount of weight on the shuttle. One of the Constructicons suggests airlocking the wounded Decepticons so the healthy ones will survive. Although not his idea Starscream (of course!) is happy to go along with it. Surprisingly, the Decepticons put it to a vote; the wounded Decepticons vote against the idea, the uninjured ones vote for it. Since the uninjured outnumber the wounded, out the airlock they go. Given that Transformers can breathe in space and that there were plenty of other planets closer than Cybertron around, it's pretty clear they could have easily Taken A Third Option if they were really inclined. Starscream just wanted to finally get rid of Megatron, who was one of the wounded. That, and Decepticons are dicks.
- In the first episode of The Mighty Ducks, the Ducks' ship is traveling through dimensional limbo. Unfortunately, the ship will fall apart unless some weight is jettisoned, and everything onboard is bolted down. Team leader Canard decides to jettison himself. Wildwing tries to stop him, but only manages to save the mask of Drake Dukane.
- That scenario that was supposed to test 'decision making' but was actually a Space Whale Aesop regarding the evils of nuclear proliferation. You know the one: there's six people but only room in the nuke shelter for five — whom do you throw out? There would usually be an obvious Red Shirt character like a priest, supposedly proving the irrelevance of organised religion. These scenarios never included the details that would matter in real life, such as who was your best buddy, who was an attractive member of the opposite sex or who was holding a firearm at the moment the crucial decision was made. It also doesn't factor in Values Dissonance. A Catholic might well decide that having a priest is far more important than having a doctor, for instance. In the end, the resulting argument is intended to make everyone conclude that nuclear war is wrong as Take a Third Option.
- There's an urban myth where people found the dead body of a man in the desert holding a piece of straw. In a line from his body are clothes and equipment. It's impossible for him to have walked and there are no tracks leading away from a vehicle. The solution to the mystery is that he was on a balloon that was descending over the desert; the passengers threw out everything they could to gain height, before realizing one person would have to go. The corpse drew the short straw.
- Another scenario meant to teach to never judge a book by the cover uses this, and runs thusly: You are in a balloon that is rapidly losing height at a rate than any impact will prove fatal for all aboard. The passengers are you, a geriatric old woman, a wealthy looking man in a suit, and a teenager about to inject himself. One person must be thrown out, but who? Turns out the old woman fought for women's rights, the businessman earns hundreds of dollars through fraud, and the teenager's actually injecting himself with insulin—he's diabetic.
- Oddly enough, none of the options ever seem to be "Heroic Sacrifice..."
- NASA attempts to avert this trope by building in several levels of redundancies and over engineering into their space vehicles. Despite this, even the Shuttle launches had several windows where any malfunction or error would result in "LOV" (Loss Of Vehicle).
- Apollo 13 actually ran into this dilemma. After the oxygen tank in the command module explodes, the crew is forced to use the life-support systems of the LEM module. Normally, this wouldn't have been a problem, but the LEM was only designed to support two people, not the full crew. note Luckily, they succeeded in MacGyvering a few ways to work around this that didn't involve murder, and NASA wanted their LEMs to have a big fat margin of error if something went awry. NASA didn't expect the LEM to have to last for 3 men for the entire mission, but it did.
- Two famous court cases in The Common Law tradition involving survivors of shipwrecks who took to the lifeboats and were charged with murder for their subsequent actions. Both cases ended with the accused being convicted of murder (albeit with vastly reduced sentences), setting the precedent that self-preservation does not excuse the murder of an innocent.
- United States vs. Holmes (a US federal case) in which sailors forced passengers (including women) off an overcrowded lifeboat.
- R vs. Dudley and Stephens (a British case 40 years later that cited Holmes) in which sailors murdered and ate the weakest member of their lifeboat crew, on the grounds that they were starving and he was likely to die anyway.
- Precedent does, however, establish that necessity is a positive defense to cannibalizing a corpse provided that the victim was already dead.
- Lawrence Oates went out into a blizzard after supplies for the ill-fated Scott Antarctic Expedition ran low, in an ultimately futile attempt to save his companions.
- The commander of a Cold War-era underground base in North Bay, Ontario would have been forced to invoke this had a nuclear bomb detonated near the base and forced it to be sealed. To prevent radiological contamination, the entire base's air supply would be sealed. Even the air-supply for the emergency generators! They had a choice: keep the generators running so that the base's air defense computers kept running, and kill everyone within hours, or keep them off, survive for weeks, but weaken the defenses of a continent?