A Feast for Crows is the fourth of seven planned novels in A Song of Ice and Fire, an epic fantasy series by American author George R. R. Martin.
A Feast for Crows picks up the tale where A Storm of Swords left off and runs simultaneously with events in the following novel, A Dance with Dragons. The War of the Five Kings seems to be winding down. Robb Stark, Joffrey Baratheon, Renly Baratheon and Balon Greyjoy are dead. King Stannis Baratheon has gone to the aid of the Wall, where Jon Snow has become Lord Commander. King Tommen Baratheon, Joffrey's eight-year-old brother, now rules in King's Landing under the watchful eye of his mother, the Queen Regent Cersei Lannister. Lord Tywin Lannister is dead, murdered by his son Tyrion who has fled the city, to lands unknown. Meanwhile, Sansa Stark is still in hiding in the Vale, protected by Petyr 'Littlefinger' Baelish who has murdered his wife Lysa Arryn and named himself Protector of the Vale and guardian of eight-year-old Lord Robert Arryn.
In the city of Oldtown, a young novice of the Citadel named Pate steals a master key from a retired archmaester and sells it to a mysterious man calling himself the Alchemist. Shortly after receiving his payment, Pate collapses and dies in the street, possibly due to poisoning.
Cersei's reign is marked by her increasing distrust of the Tyrells, particularly her son's new wife Margaery. Increasingly paranoid over a prophecy she believes foretells the deaths of her children and herself at the hands of her missing brother Tyrion, she develops a dependency on alcohol. To settle the crown's debts to the Faith, she agrees to the restoration of that religion's military order, the Faith Militant. A scheme to have the Faith put Margaery on trial for largely-invented accusations on adultery goes wrong when the newly-powerful religious leadership arrests and imprisons Cersei herself on similar (and accurate) charges.
Cersei's brother and one-time lover Jaime travels the riverlands to re-establish order and royal control in the war-torn region. He has become somewhat estranged from his sister and newly concerned with his own honor, which he believes is tarnished by past misdeeds. After ending the siege of Riverrun, one of the last holdouts against his family's authority, he receives word that Cersei wants him to return and defend her in a trial by battle, but burns and apparently ignores the message.
On the Iron Islands, Euron Greyjoy is chosen king due to his promise that he can summon dragons that will help the islanders conquer all of Westeros. He sends his brother Victarion east to woo Daenerys Targaryen, but a bitter Victarion instead plans to marry her himself. Meanwhile, in Dorne, a disastrous attempt by Arianne Martell to crown Myrcella Baratheon as queen of Westeros under Dornish law leads Arianne's father Doran to reveal to her that he has his own subtler plan for vengeance; her brother Quentyn has gone east to bring back "Fire and blood." The attempt has also left Myrcella's face scarred, straining the new allegiance with House Lannister and the Iron Throne, as a member of the Kingsguard is on his way to Dorne with the head of The Mountain.
Brienne of Tarth's quest for Sansa Stark leads her all over the riverlands, where she observes the devastation and villainy that the war has wrought among the smallfolk. Eventually captured by the Brotherhood Without Banners, she is sentenced to death by her former ally, now corpse-like Catelyn Stark, who wrongly believes Brienne has betrayed her. Brienne is told she will be allowed to live if she agrees to find and kill Jaime Lannister; refusing, she and some of her companions are hanged, and as the nooses strangle them she screams out one unrevealed word.
Samwell Tarly is sent to the Citadel for training and to learn what they know of the Others. Accompanied by Maester Aemon, Dareon (another man of the Night's Watch), and the wildling girl Gilly, he travels to Braavos, where Aemon's ill health causes them to miss their boat and Dareon loses interest in their mission. Sam, Aemon, and Gilly eventually resume their voyage to Oldtown; however while they are en route Aemon dies and Sam and Gilly become lovers. At Oldtown, Sam becomes a novice, and meets someone who claims to be Pate, the novice murdered in the prologue.
Arriving in Braavos, Arya Stark finds her way to the House of Black and White, a temple associated with the assassins known as the Faceless Men. As a novice there, Arya attempts to master their belief that Faceless Men have no true identity by posing as a girl named "Cat of the Canals;" however, her former identity sometimes asserts itself, as when she kills Dareon for abandoning the Night's Watch (and Samwell Tarly). The morning after her return to the House of Black and White following this murder, she admits that "Arya" committed it, and is given a glass of milk meant for "Arya." After drinking, she wakes up the following day blind.
In the Eyrie, Sansa Stark poses as Petyr Baelish's bastard daughter Alayne, befriending young Robert Arryn, managing the household for her "father," and receiving informal training in royal politics from him. He eventually reveals that he has betrothed her to Harrold Hardyng, Robert's heir; when the sickly Robert dies, Sansa will reveal her true identity, and reclaim her family stronghold of Winterfell.
As the fourth book ends, a winter that will most likely last for years descends upon Westeros, promising famine and suffering for an already war-ravaged land.