Character shields (also known as plot armor or plot shield) are plot devices in films and television shows that prevent important characters from dying or being seriously injured at dramatically inconvenient moments. It often denotes a situation in which it strains credibility to believe that the character would survive.
However, an argument in favor of the character shield for films (not so for extended series) is that the narrative follows a given character because they survive through the entire arc of the story. That is to say, the audience could have followed any character, but the story chooses to follow the one who will be the most helpful in transmitting the events -- often turning out to be a secondary character who narrates the last scene, such as in Red Dawn and We Were Soldiers, each of which is capped by comments from a character who first appears partway through the action.
In some film franchises, character shields are valid only for the duration of a single film, as major characters are killed off to wipe the slate clean for a new film. Alien 3, for example, begins with the deaths of Newt and Hicks, although the whole point of the previous film was their rescue.
The killing of a major character also keys in to the audience that a situation is dire, or that the killer is a villain to be taken seriously. Sometimes, as in Scream 3, Friday the 13th Part II, or Halloween: Resurrection, a star of the earlier film will appear at the beginning of the new film in a cameo, only to be killed off. The fifth season of the television series 24 famously used such a device to wipe out almost every cast member who had participated in the first three seasons.
Sometimes a character shield even allows a character to return from the dead, though this is usually accomplished through technological or supernatural means in sci-fi and fantasy works. Notable examples include the sacrifice of the character of Spock in Star Trek II: The Wrath of Khan and his return in Star Trek III: The Search for Spock, and the death of Gandalf in The Fellowship of the Ring, and his return in The Two Towers.
Minor characters that repeatedly survive dangerous situations but do not express other major character traits are called Wedge-type characters. This is named after Wedge Antilles from Star Wars: an entirely non-integral, "I-Was-There-Too" character who survives the three original Star Wars films despite taking part in a pivotal battle in each film, during which other characters of equal or greater standing in the story were consistently killed off.
Star Wars also featured a character shield who had originally had a larger part (cut to a few seconds for the sake of brevity), Luke's boyhood friend Biggs Darklighter. Though later versions of the first film restored Biggs' part, the original release features unexplained familiarity between Luke and Biggs in the battle over the Death Star (and Luke's sorrow over Darklighter's fiery death).
This character shield also applies to vehicles (such as cars, space ships or jet fighters) in which minor characters' vehicles can be destroyed in a few shots, yet the protagonist's (who may be using the same type of vehicle) can often survive massive amounts of damage (and in some cases also boasts better maneuverability). An example of this is the protagonist Jason Bourne's vehicle from the car chase in the film The Bourne Supremacy, where despite being involved in multiple traffic accidents which incapacitate his pursuers, his car is still able to operate. The Yamato in the anime Space Battleship Yamato also has a similar character shield where it survives grievous damage while other, sometimes larger and newer ships are easily destroyed by enemy fire.
A character shield can also be referred to as "PC glow", referring to the metaphorical glow around player characters (PCs) that shields them from commonplace death. In many console RPGs, resurrecting a fallen player character is fairly trivial when the PC dies in ordinary battle; only special circumstances may kill a character with PC glow. A party member may be permanently killed in a cut scene by a primary villain or by giving up his or her life to save the other party members or the world, but never by generic enemy grunts in a generic battle. Commonly, instead of being "killed" by an enemy, a defeated character will be simply "knocked out" (KO'd) or rendered unconscious so as not to minimize the finality of death. This is commonly seen in RPGs where attacks in a normal battle scene are more or less nonfatal (such as the standard soldiers in Final Fantasy 7, whose guns deal negligible damage). However, during cutscenes, such weapons can be fatal.
In the DragonLance series of AD&D game modules, if the players use the pre-generated characters the "obscure death" rule is in force for the first few modules. Characters can appear to die, but must then be returned to the game to avoid plot holes. For example if a character is killed in battle, he's merely knocked unconscious. If he falls from a high cliff, he'll be saved by striking a ledge and rolling into a hidden cave; thus to rejoin the party later. Some NPCs also fall under this rule. The Knock Out rule is used on story critical NPCs in the video game Oblivion.
In D&D, characters repeatedly spared from death by the DM, usually in order to complete a story arc, are described as "wearing PC shirts".
The same idea is used in many video games, with most of the NPCs having shields (such as very high character levels or invulnerability), to prevent glitches and preserve the flow of the game. For example, it would cause a plothole if a character appears in a cut scene later in the game, but was killed during play; for this reason, Halo 2's Sergeant Johnson (as just one example) is invincible during any gameplay he participates in because he is an integral part of the plot; in fact, he encourages the player to "Hide behind me!" during the opening battle. Likely because of his invulnerability various plot devices are often employed to split Johnson and the player apart; this is not unusual as many game developers tend to come up with ways to mitigate the absurd advantage an exploitive player could make of an invincible allied NPC. He was not invincible during the events of Halo: Combat Evolved however, and an Easter-egg ending depicts him stranded on Halo with an Elite when it is destroyed by the Pillar of Autumn. This ending is non-canon; Johnson's survival is depicted in the novel Halo: First Strike. In Deus Ex: Invisible War, important characters appear either through a holographic communication or in areas where the player's weapons are disabled (preventing the player from killing them). It should also be noted that in Final Fantasy Tactics, many plot-important characters who have some degree of importance at the current stage of the game and/or through later events, often appear as 'Guests', who are immune to death. Instead, they are simply knocked out and may be kept KO'ed without fear of penalty. Good, easy-to-recognize examples are Delita Hyral (who remains a guest to the very end) and Algus, who joins the player as a guest for a few missions, then becomes an enemy and may die.
Another version of the above is when the player is given the objective to protect a certain NPC. This is often employed in Warcraft and Starcraft series of games. Whenever the player is given a character important to the story to control, one of the objectives is to protect said character from death (otherwise the mission is failed).
In the video game Half-Life 2 and its subsequent Episodes, at various points the player is assisted by various NPCs. NPCs which are vital to the storyline, such as Alyx Vance, are given a very rapid health regeneration system - others, like Dog, are given a very large amount of health points instead. The death of a story-vital NPC results in failure; however, it is very difficult to allow such an event to happen.
In the video game Final Fantasy XII, one of the main characters Balthier states that as he is the main character in his "story" he cannot die. After the final battle of the game, he is seemingly lost, contradicting his theory, but later delivers a letter to the other main character Vaan stating that he indeed survived.
In Baldur's Gate II: Shadows of Amn, some characters at certain times are unable to die. For example, during Chapter 1, the Mage-Thief Imoen cannot die. When she reaches 1 Hitpoint, she will panic and run away, regardless of any further damage done to her, because she is of vital importance to the plot later on. Research has shown that characters in the game that cannot die, are wearing an item that prevents their hitpoints from falling below 1.
Alternatively, in the satirical internet-comic Concerned, based on Half Life 2, the main character survives many certain death situations (fired out of a cannon etc.) for no reason, but at the end, it is revealed that he had a god-mode cheat on which prevented his death until the point where he had to die.
The PC Game Morrowind allowed the killing of major NPC's however if this was done the player was given a message that the 'prophecy' was broken. This meant the main quest and effectively the game could not be completed in the traditional sense. The player could literally "change the course of history" by completing the game in a very obscure and MUCH more difficult way. The sequel Oblivion revised this to make main NPC's unkillable, they could only be knocked unconscious. This was to prevent disruption of the plot by the player or random encounters between the NPC and monsters
In Metal Gear Solid 3: Snake Eater, the character Revolver Ocelot may be defeated after a battle but never killed. As the game is prequel, any death of a major character results in the player losing the current game and the game declaring a 'Time Paradox'.
The wrestling game WWE Smackdown Vs. RAW 2006 has a novel character shield. As the plot only accommodates a championship win at Wrestlemania, if a player successfully wins a championship before then he is stripped of it.
In many video games, playable or allied characters can die during battle, but are easily resurrected. In the Final Fantasy series, if a character dies in battle, they can be brought back using a spell or the "phoenix down" item, with no explanation for why these items can apparently not be used on anyone who dies during a cutscene. In the X-Men: Legends series and Marvel: Ultimate Alliance a playable character who dies can be resurrected at any extraction point for a small fee. In the Kingdom Hearts series allied characters Donald Duck and Goofy can die in battle, but will come back to life automatically after a period of time. This is also true of Alphonse Elric, a non-playable ally who battles alongside Edward Elric in the Fullmetal Alchemist games. Ed can also revive Al quickly using alchemy at any time during a battle. One notable exception is the Fire Emblem series, where characters who die cannot be resurrected.
In the webcomic Bob and George, the title characters have actual shields (plastic-wrap force-fields), to protect them, as well as being protected from pretty much anything, explained by the fact that as title characters, they cannot die. Non-integral characters flaunt this by having a ring of stars surround them which they call "Star Power", claiming they cannot die because they are fan favorites. Star Power is destroyed by the threat of Communism, a reference to Joe McCarthy. This phenomenon was the center of a story arc, in which George goes back in time to discover the explanation behind one of his more far-fetched deus ex machina.