Driving Question

"Trinity: "I know why you're here, Neo. I know what you've been doing. I know why you hardly sleep, why you live alone, and why night after night you sit at your computer. You're looking for him. I know, because I was once looking for the same thing. And when he found me, he told me I wasn't really looking for him. I was looking for an answer. It's the question that drives us mad. It's the question that brought you here. You know the question, just as I did." Neo: "What is the Matrix?""

- The Matrix

When a core element of the plot is a mystery. The most common variation would be a detective murder mystery, but also very popular in Noughties Drama Series', Jigsaw Puzzle Plots and Survival Horror. In many cases the question is equivalent to, "What the hell is going on and why?" which taken far enough makes for an Ontological Mystery.

See The Un-Reveal and The Reveal. Leave the Plot Threads Hanging is what happens when the answers aren't all they are cracked up to be. Failure Is the Only Option to answering the question in a TV series where the question is central to the show. Too many can lead to a Kudzu Plot. The Chris Carter Effect is what happens when fans give up on the writers' ability to answer these questions.

See also Central Theme, Detective Drama, Mystery Fiction, and Mystery Literature.

Anime and Manga

 * 20th Century Boys: While it's far from the only one, and it's answered well before the series is over, the one that comes to mind first is Friend's identity.
 * Ergo Proxy: What are the Proxies?
 * Neon Genesis Evangelion: Due to the Mind Screw, there are many, but most prominently the truth about the Evas.
 * The other major series-spanning mystery is that of Gendo and SEELE's true motives.
 * The second half of Monster uses this heavily. While minor versions of this are used every once in awhile to heighten suspense, increasing knowledge of Johan's history provides heavy hints that he's up to something. What the characters want to know is what.
 * Spiral: What are the Blade Children?
 * Mahou Sensei Negima: Where is Nagi Springfield, and why has he been MIA for the past decade?
 * Ghost in the Shell: Who is the Puppet Master, and what does he/she/it want?
 * Ghost In The Shell: Innocence: Why did the Hadaly gynoids kill their owners?
 * Ghost in the Shell: Stand Alone Complex: Who is the Laughing Man, and what does he/she/it want?
 * Paranoia Agent: Who is Shonen Bat/Li'l Slugger?
 * Code Geass: In the first season, who killed Lelouch's mother and why? In R2, it's what exactly is C.C.'s wish and, ultimately, where does Geass itself come from?
 * Digimon Tamers: What is Culumon's purpose?
 * Digimon Savers: What hapenned to Daimon Suguru in the expedition 10 years ago?
 * Clannad: What is this girl we keep on seeing, and what is her purpose? What are these Light Orbs we also see? And how are they connected?
 * Higurashi no Naku Koro ni: Why is Hinamizawa stuck in a Groundhog Day Loop? Why do the main characters keep on going batshit crazy and murderous? Who is behind the town's annual deaths?
 * Naruto:
 * Arisa: Who is the King?
 * Black Butler: Who is the proper target of Ciel's revenge?

Film

 * Citizen Kane: What does "Rosebud" mean?
 * Even though everybody knows.
 * Green Zone: Who is "Magellan"?
 * "What is The Matrix?" and "It's the question that drives us" are two iconic phrases from The Matrix.
 * However, the resistance already knows the answer and tells it both Neo and the audience within the first minutes of the first movie. The search for the answer becomes completely irrelevant for the rest of the series.
 * The Vanishing: What happened to the missing woman?
 * The Usual Suspects: Who or what is Keyser Soze?
 * Shutter Island: What happened to the escaped patient, and what is really going on at the titular treatment facility?
 * Exam: There is one question before you, and only one answer required.
 * Inception: Is this a dream or reality?

Literature

 * Each Harry Potter book has its own.
 * Sorcerer's Stone: What is Snape after?
 * Chamber of Secrets: Who opened the Chamber?
 * Prisoner of Azkaban: What did Black do, precisely?
 * Goblet of Fire: Who put Harry's name in the Goblet of Fire?
 * Order of the Phoenix: What is the weapon?
 * Half Blood Prince: What is Malfoy planning?
 * Deathly Hallows: Where are the Hallows and Horcruxes?
 * The Dark Tower. What's in the final room of The Dark Tower?
 * There also used to be "Why is the Dark Tower and the rest of reality decaying?" but we eventually learn that
 * Atlas Shrugged: Who is John Galt?
 * The 1st of the Otherland books uses several of these at once. What is happening with Rene's brother? Why is Paul switching dimensions? What is the purpose of this Grail organization, and who is their leader? What Mr. Sellars is up to, and many others. Because this book is widely considered to be an oversized prologue to the later ones, the answers are pretty well known.
 * The Chronicles of Amber (Series One): Who shot Corwin's tires? Who is behind the Dark Road?
 * interestingly enough,
 * Under the Dome by Stephen King: where did the dome come from, and why is it there?
 * Stephen Fry's The Hippopotamus: What does Jane want Ted to look for?
 * Twenty Thousand Leagues Under the Sea starts with, "What is sinking ships?" and gets narrowed down to, "Where did Nemo come from and why is he attacking ships?"
 * The Mysterious Island: Who or what keeps helping the survivors?
 * A Void: Is Anton missing or did he kill himself?
 * The novel also asks whether or not it was a suicidal act and then repeatedly asks if he killed himself in various ways.
 * Futuretrack Five: The question starts out as "who is Scott-Astbury?" Since apparently he's some kind of Manipulative Bastard Chessmaster and the only person on record of that name is a publicly-known utter tit. It then becomes "What did Scott-Astbury do?"
 * The second half (Power of Three and Omen of the Stars) of Warrior Cats has many questions. "Where did the three come from?" "What is their purpose?" "Who is "

Live Action TV

 * Dexter
 * Season 1. Who is the Ice Truck Killer?
 * Season 3. What's the deal with Miguel/Who is the 'Skinner'?
 * Lost thrives on this. The Myth Arc is about the protagonists getting dropped in the middle of these strange, inexplicable and in some cases scientifically impossible occurances and trying to puzzle out the answers to these questions. And there are many questions: "Where are we?" "What is the monster?" "How are people being healed?" "Will we ever escape the Island?" "What is the Island?" "Who are The Others?" "What's in the hatch?" "Should they keep pushing the button?" "What crashed the plane?" "What are the Whispers?" And due to the focused viewpoint, a lot of them don't get explicit answers.
 * Season 6, however, cuts to the heart of it and makes it clear that the show's Driving Question is actually "Why are these people on the Island?" The answer has many facets that touch on both the A-story of the show and the thematic drive of the show.
 * Twin Peaks: Who killed Laura Palmer?
 * Veronica Mars: Season 1: Who killed Lily Kane?
 * Season 2: Who blew up the bus?
 * Season 3: Both "Who is the serial rapist?" and "Who killed "
 * In the first season of The Sarah Connor Chronicles, the Driving Question was how to find and destroy the Turk. By the second season, the question instead came in the form of a Room Full of Crazy drawn by a dying resistance soldier, and the cast's attempts to figure out the meaning of all the names and places written there.
 * And the overarching Terminator question: How can SkyNet be stopped?
 * The Prisoner: Who is Number One? Who runs The Village? Why did Number Six resign?
 * Burn Notice: "Why was I burned?"
 * White Collar: What happened to Kate?
 * Monk: Who killed Trudy?
 * Ashes to Ashes: What happened to Sam Tyler? (Whilst this was only an actual Driving Question in the third and final series, it had been brought up very briefly in the first episode of the first series.)
 * The X-Files: What happened to Mulder's sister? What is the truth about the aliens?
 * FlashForward: Who caused the blackout and why? And later,
 * Doctor Who series 5: What is causing the cracks in time?
 * Series 6 introduced the first question, the oldest question in the universe, a question hidden in plain sight, a question that must never, ever be answered:  The Doctor will eventually be forced to truthfully answer this question, and in doing so... well, let's just say the results would be bad.
 * Fringe: The first season was driven by the question, "What is the Pattern, and what does it mean?"
 * Babylon 5:
 * Season One: What do you want?
 * Season Two: Who are you?
 * Season Three: Why are you here?
 * Season Four: Do you have anything worth living for?
 * Season Five: Where are you going?
 * Rather a driving sentence than a question in Homeland - "An American prisoner of war has been turned." The question is, is it true?
 * Castle: Who ordered the hit on Beckett's mother, and why?
 * Reimagined Hawaii Five-0, second season: Who or what is Shelburne?

Video Games

 * Planescape: Torment. You wake up without knowledge of who you are, what you're doing here, and why you can't remember anything. The first order of business is to fix that, and it takes most of the game.
 * The Arc Words "What can change the nature of a man?" would also qualify.
 * Baldur's Gate: Who is the "armoured figure"? Why is he trying to kill the Player Character? What do all these dreams and portents mean? And what is the Iron Throne trying to do and what does that have to do with any of the other questions?
 * In the sequel it's "Who is Jon Irenicus and what does he want from you?"
 * Neverwinter Nights mod The Bastard of Kosigan: Who is killing off the Kosigan family? And what can I do about it?
 * A Dance With Rogues chapter 2: Where is Master Nathan, and how can I rescue him?
 * Knights of the Old Republic: What and where is the Star Forge?
 * Knights Of The Old Republic 2: Where are the lost Jedi Masters? Who is Kreia? And what the hell is going on?
 * Jade Empire: Did Death's Hand have the Emperor's backing or has he taken over? Who is the scaly blue lady that keeps appearing to me in visions? How can I rescue Master Li?
 * Mass Effect 1: What and where is the Conduit? Also: What are the Reapers?
 * Mass Effect 2: How do you get through the Omega 4 Relay? More importantly: How do you accomplish your mission to destroy the Collectors and get back in one piece?
 * Mass Effect 3: How are we going to stop the Reapers from tearing Earth (and the galaxy as a whole) a structurally superfluous new behind?
 * Dragon Age Origins: Where is the Archdemon and how do we kill it?
 * Awakening: Why are Darkspawn still attacking even after the Blight ended?
 * Witch Hunt: What happened to Morrigan?
 * Dragon Age II: How did Hawke become the Champion and what does it have to do with the downfall of the Chantry?
 * Legacy: Who or what is Corypheus and what is its connection to the Hawke family?
 * Mark of the Assassin: What did Hawke do to sour Kirkwall's relations with Orlais?
 * Silent Hill: Several of the games run on one over-riding question.
 * Silent Hill 1: "Have you seen a little girl? She just turned seven last month. Short, black hair . . ."
 * Silent Hill 2: Where is Mary, and what does she want?
 * Silent Hill 3: Averted for the most part. The protagonist Heather wants nothing to do with anyone—at least until
 * Silent Hill 4: What does the room want from Henry?
 * Silent Hill Origins: Why can't Travis leave Silent Hill?
 * Silent Hill Homecoming: Why is Alex's life such a mess?
 * Silent Hill: Shattered Memories: Same as Silent Hill 1, although the answer is extremely different.
 * Metal Gear has several, the most prominent being "Who are the Patriots?" and perhaps "Who is Ocelot really working for?"
 * Baroque: "Who is the protagonist, and what was his sin?"
 * Chrono Cross: Specific to players who already played the first game - "What's going on and how does it relate to Chrono Trigger?"
 * Final Fantasy X: "What happened to Zanarkand?"
 * Armored Core:
 * For Answer: What do we do about the environmental destruction of Earth, and how do we save humanity (Or do we)?
 * Armored Core 3: What's going on in Layered? Is the Controller really malfunctioning?
 * Armored Core Silent Line: What's beyond the Silent Line?
 * S.T.A.L.K.E.R: Shadow of Chernobyl: Who or what is The Strelok? And why should you kill him?
 * F.E.A.R.: Who is Alma and what relation does she have with you?
 * Dead Space: What happened to the crew members?
 * Dead Space 2: What did Isaac Clark inadvertently do?
 * The entire Half Life franchise: What the hell is the G-Man trying to achieve? And what does he want from Gordon?
 * Episode One: What did Alyx steal from the Combine?
 * Episode Two, second half: What does the G-Man's message to Eli mean?
 * Batman: Arkham City: For the first part of the game, what is Protocol 10?
 * Psychonauts (only the Milkman Conspiracy level): Who is the Milkman?
 * Dark Souls: How can I save the flames that sustain life as we know it? Another question presents itself later:
 * Persona: Who is this girl calling herself Maki, and what did Kanbari do to the world?
 * Persona 3: What caused the Dark Hour?
 * Persona 4: Who's responsible for the killings in Inaba?
 * Ghost Trick: Sissel has one driving question throughout the story. "Who am I?"

Webcomics

 * Gunnerkrigg Court: What exactly is the Court? (Which in turn is connected to several sub-questions: What was Surma's and Anthony's history with the Court? Who is that ghost in the gorge, and why is she trapped there? What the hell is Zimmy's deal?)
 * Sluggy Freelance: What is Oasis? It doesn't drive the whole comic, but it does so several stories in it, and so far has remained unresolved for a long, long time. There are also other questions that drove single storylines but have been resolved, eg. "Where is Teknokon One?" and "What are the ghouls?" (There are also other questions, such as "What is Bun-bun's past?" that are just as mysterious but don't actually drive the story.)
 * El Goonish Shive: Why are the French Immortals amnesic? Who summoned the flame summon and why? The last question drives the New And Old Flames storylines. Other big questions exist but have been resolved, their solutions are not being actively pursued in universe or are not pondered by the characters themselves.

Western Animation

 * The Zeta Project: What makes Zeta more than a machine? Ro has her own driving question: "Where is my brother?" which actually gets resolved halfway through season two.