Petyr Baelish
Littlefinger: a lord of small birth and enormous ambition who rose from nothing to Master of Coin, financing the crown and his own schemes in equal measure. He knew Catelyn Tully as a boy and never forgot her.
The fuller tale
Petyr Baelish comes from almost nothing, and never stops billing the realm for it. His great-grandfather was a Braavosi sellsword; his inheritance was a windswept scrap of the Fingers so small that his mocking boyhood nickname — Littlefinger — described the estate as much as the boy. Fostered at Riverrun as Lord Tully's ward, he fell absolutely in love with Catelyn Tully, challenged her betrothed Brandon Stark for her hand, and was nearly cut in half for the presumption — surviving only because Catelyn begged for his life. Every historian of the saga's wars eventually arrives at the same conclusion: the whole catastrophe is downstream of that duel. The boy who lost it decided that if the realm's rules made him a joke, he would learn the rules better than anyone alive, and then sell them.
His ascent is conducted through the one force Westeros pretends not to run on. Customs posts, brothels, loans, exchange rates — Baelish masters money while the great houses master jousting, rises from collector to Master of Coin, and makes himself indispensable by making the crown's finances incomprehensible to everyone but himself. The books eventually audit him: the crown's debt is not mismanagement but architecture, a web of obligations in which half the realm's lords are his debtors, his partners or his creatures. He staffs the court with people who owe him. He knows what happens in his brothels and who it happens with. By the time the story opens, the least martial man in King's Landing is armed to the teeth.
What the realm learns far too late is that Littlefinger's true product is chaos. The saga's inciting mysteries — Jon Arryn's poisoning, the catspaw dagger sworn to Tyrion, the letter that set Catelyn against the Lannisters — resolve, one by one, to the same smiling address. He teaches the lesson himself, in the show's most quoted piece of villain philosophy: chaos isn't a pit, it's a ladder. He betrays Ned Stark at the moment of maximum trust — knife to the throat in the throne room, gold cloaks bought and paid for — brokers the Tyrell alliance that wins the Blackwater, supplies the poison that kills a king at his own wedding, and leaves every disaster one rung higher than he entered it.
Sansa Stark is where the ledger and the wound intersect. Half his obsession with Catelyn's daughter is strategy — a Stark heir in hand is the North on a chain — and half is something queasier that the story never lets him untangle. He extracts her from King's Landing after the Purple Wedding, murders his own new wife Lysa Arryn within days of the marriage for the crime of threatening the girl, and installs himself as Lord Protector of the Vale with Sansa as his apprentice, teaching her the game he means her to play beside him. It is his one sentimental project, and sentiment is the single commodity Littlefinger has never learned to price. The pupil watches everything — including him.
His endgame is a bet that the old tricks scale. Selling Sansa to the Boltons buys him the North's gratitude when the Boltons fall; delivering the Vale's knights to the Battle of the Bastards buys him a seat at Winterfell; and once inside, he sets about his oldest routine, whispering sister against sister while positioning himself beside the future queen. But Winterfell is the wrong room for it. He is playing the letter-and-rumor game against a girl trained by his own tutelage, another trained by the Faceless Men, and a third who is the realm's memory made flesh — an audience on whom the ladder's every rung is visible. Littlefinger's story is the saga's cold joke about self-made men: he really did rise from nothing, on pure intelligence and nerve, and the person his climbing most thoroughly educated was the one standing at the top of the ladder when he ran out of rungs.
The page and the screen
The show's Baelish is the books' Baelish with the mask half off. On the page he is charm all the way down — a small, quick, endlessly amusing man whom nobody believes dangerous, which is the entire trick; readers learn his depths only when point-of-view characters fall through them. Aidan Gillen's version telegraphs menace from the first season, and the show compensates by handing him scenes the books never staged: the chaos-ladder monologue, the direct confessions to Sansa and Ros, the open sparring with Varys across the throne room. The largest divergence is structural — the marriage of Sansa to Ramsay Bolton is pure invention, and book readers note it requires show-Littlefinger to do the one thing his book self never does: surrender his most valuable asset into hands he cannot control, uninformed.
In the published novels his game is still very much afoot. He rules the Vale as Lord Protector, keeps Sansa hidden in plain sight as his bastard daughter Alayne, and is maneuvering her toward a marriage with the Vale's heir, Harrold Hardyng — a plan whose endpoint, revealing Sansa Stark to claim both North and Vale at a stroke, the show compressed and discarded. Book readers therefore know a Littlefinger who has not yet made a single fatal mistake.
In the show, season by season
Season Three. In The Climb — The ladder is all there is.
Season Four. In First of His Name — The whole war, it turns out, started with his lie and Lysa's letter. In Mockingbird — "Only Cat." And the Moon Door swallows a jealous heart.
Season Five. In High Sparrow — Sells Sansa north the way he sells everything: smiling.
In the books
A Game of Thrones. In The Wine and the Boar — "I did warn you not to trust me."
A Storm of Swords. In The Purple Wedding and the Trial — The purple wedding's quiet architect, per the Queen of Thorns' design.
Where they stand, season by season
Their fate — if death has found them, it is written here. Open at your peril.
The show: Judged and executed at Winterfell (alive in the books) (S7·E7)
The man who started the whole game — Jon Arryn's poison, the dagger, the letter — was tried in Winterfell's hall by the sisters he'd spent years playing against each other. Sansa passed the sentence; Arya's blade crossed his throat mid-plea.
The show ends him in the hall of the family he spent a lifetime dismantling. At Winterfell, believing his sister-against-sister campaign is working, he attends what he thinks is Arya Stark's trial — until Sansa, presiding, turns the charges on him: murder, and treason. The indictment is the series' full accounting, delivered by his victims' daughters with the realm's memory sitting witness — Lysa's poisoning of Jon Arryn at his word, the dagger, the betrayal of Ned, the sale of Sansa — with Bran supplying the details no living witness could. Littlefinger cycles through every tool that ever worked: denial, bargaining, a plea to Sansa's history with him, and finally, on his knees, begging. Sansa passes the sentence — she is a slow learner, she tells him, but she learns — and Arya opens his throat with the Valyrian dagger that began his game, mid-plea. In the published books he is alive, unsuspected, and winning: Lord Protector of the Vale with the realm's most valuable heiress on his arm and his fingerprints still invisible on every body. His show death is the series' promise about how his story must end; the books have yet to sign it.