Dracarys (SPOILERS BECAUSE DUH!!!!!!!!)
Daenerys Targaryen continues on her quest to reclaim her birthright by using the fortune she took from Xaro in Season 2 to purchase for herself an army. She comes across a suitable fighting force of slave soldiers called The Unsullied, eunuchs who have been trained since a very young age to be ruthless killing machines. While there, she comes across a Targaryen loyalist, Ser Barristan Selmy, who offers his services to Dany. Unhappy that the Unsullied would be "sold" to her, she plots to trick the Slave Masters who own them to sell her them in exchange for one of her dragons. As the exchange takes place, Dany turns the Unsullied against the Slave Masters and has them kill them, while her growing dragon roasts the Slave Masters. She offers the Unsullied their freedom and they choose to continue serving her. Dany decides to liberate more of the slaves in Essos before returning her focus to Westeros and reclaiming her throne.
With her betrothal to King Joffrey ended, Sansa Stark hopes against hope for a way to be freed from her imprisonment in King's Landing and may have found a way out with the help of Lord Petyr Baelish (AKA Littlefinger), who was once enamored with her mother enough to challenge another man for her hand in marriage. Littlefinger plots to bring her with him when the Lannisters send him to the Vale to marry Sansa's unstable Aunt Lysa and bring her on side in the war. Thus begins a tug of war over the fate of Sansa Stark, as many begin to see her and her potential claim to Winterfell (should Robb Stark die) as a key to controlling the fiercely independent North.
Arya Stark and her friends continue to run from the Lannister soldiers they were captives of and make their way deep into the Riverlands. Arya decides to bring herself, Gendry and Hot Pie to Riverrun, where her Grandfather Hoster Tully rules defiantly on behalf of her brother Robb. While on route to the castle fortress, the group is picked up by the Brotherhood Without Banners, a Robin Hood-like group that fights on behalf of the smallfolk. When the newly captured Sandor Clegane (AKA the Hound) rats out Arya's true identity to the Brotherhood, they plot to ransom her at Riverrun, but not before bringing the Hound to trial for his many crimes. Led deep into the forests of the Riverlands, the Hound faces off against Beric Dondarrion, who has taken on the faith of the Lord of Light with the aid of his longtime friend Thoros of Myr, a red priest with the power of resurrection. Despite the Hound winning his trial by combat by killing Beric, Thoros revives Beric with his powers and allows the Hound to go free.
Despite having wed the love of his life and never lost a battle, Robb Stark's war effort could not be in worse shape. With Stannis's defeat at the Blackwater and the swelling ranks of the new Lannister-Tyrell alliance combined with Theon Greyjoy's betrayal and subsequent "murder" of his brothers Bran and Rickon, Robb is forced to chase the remnants of the Lannister forces in the Riverlands, looking desperately for a way to fight without drawing the might of the Southern Lords against him. Robb can also see his own men losing faith in him, as the bloodthirsty Lord Karstark demands justice for his dead sons and Lord Roose Bolton seeming to fuel Robb's lust for battle. Robb ceases all battle measures when he learns of his grandfather, Lord Hoster Tully's passing. With Lord Bolton guarding the retaken castle of Harrenhal, Robb takes his wife Talisa, his mother (still a prisoner for her freeing of Jaime Lannister last season), and his most loyal men to Riverrun to attend to the funeral and bring the Tully's fully into his cause. While there, Lord Karstark murders two Lannister squires as payment for his dead sons. Robb calls his actions treasonous and beheads him, losing the support of the Karstark armies and weakening his numbers exponentially. With little choice, Robb must make amends with the Freys, whom he was supposed to marry a daughter of.
Jon Snow is taken by Ygritte and her scouting party to meet the leader of the "Freefolk", a former Night's Watch brother named Mance Rayder. Jon lies to Mance and tells him he wishes to stop the Night's Watch from further increasing the ranks of the Undead by warring with them and is welcomed into the group. Despite being watched over by Ygritte and Mance, many of the Wildlings do not trust Jon and suspect him of being a traitor. Before they can complete their task by scaling the Wall and leading a party of Wildlings south of the border, Ygritte forces Jon to sleep with her, thereby making him "hers" by the laws of Gods and Men, while also proving that Jon was indeed an oath breaker. Jon and Ygritte, alongside more Wildlings, scale the Wall and finally make it back behind the wall.
The Great Ranging was a complete disaster, which forces Lord Commander Mormont to lead his broken and starving men back to a relatively friendly wildling village known as Craster's Keep. Craster is icy towards them and treats the men horribly, prompting a mutiny to break out among the brothers of the Night's Watch. The Lord Commander is killed and those loyal to him are either killed or captured, save for Samwell Tarly, who flees the camp with one of Craster's daughters, Gilly and her newborn son by her father, whom she names after Sam. While fleeing back to the Wall, Sam and Gilly are set upon by a White Walker, who seeks to use the infant to swell their ranks of undead warriors. Sam, desperate to defend Gilly and her son, uses a Dragonglass Dagger to stab the creature, which causes it to unexpectedly explode on impact. Sam decides to bring the weapons to the Wall to warn the others about how to defeat the incoming army of the dead.
A prisoner of the Boltons, Theon Greyjoy is beaten, tortured, humiliated and irreparably damaged during his time in captivity, chiefly at the hands of Ramsay Snow, Roose Bolton's bastard son. Emasculated, beaten and tormented for months on end, Theon finally capitulates to becoming Ramsay's manservant, taking up the name Reek instead of Theon to prove how truly worthless he was.
Formerly prisoners of Theon, Bran and Rickon continue their way to find Jon at Castle Black, along with the simple Hodor and the Wildling Osha. While on their way, the group is found by two loyal bannermen named Meera and Jojen Reed. Jojen encourages Bran to seek out the Three-Eyed Raven he's seen in his dreams, while Osha feuds with the Reeds about wanting to keep Bran safe by bringing him to Jon at Castle Black. Ultimately, Bran decides that he and Rickon need to separate for their safety and Osha and Rickon leave the group to journey to the Last Hearth and be under the protection of House Umber, while he, Jojen, Meera and Hodor would continue to seek out the Three-Eyed Raven.
Tyrion Lannister finds himself not being given the gratitude he feels he deserves for his successful defense of King's Landing, as he has been essentially cast aside upon the return of his father, Lord Tywin, to the capital. After failing to convince his father to name him as the heir to the ancestral Lannister fortress of Casterly Rock, Tyrion finally is "awarded" with Littlefinger's old position as Master of Coin and is tasked with getting the crown's finances in order, a seemingly impossible task due to the reckless spending of Robert Baratheon and the ongoing war.
On behalf of Catelyn Stark, Brienne of Tarth leads Jaime Lannister back to King's Landing to ransom for her daughters. The two do not get along well, with Jaime constantly insulting Brienne about her feelings for Renly and her looks and Brienne calling Jaime out for his dishonor. While on their way, the two are found and captured by Bolton men. As the Bolton men plan to rape Brienne while on their way to Harrenhal, Jaime lies to them by telling them that Brienne's family was incredibly wealthy and would pay her weight in sapphire to ensure her safe return. Despite believing his lies, the Bolton flunky (named Locke) decides he's heard enough of Jaime for one life time and slices off his sword hand, crippling Jaime and sending him into a spiraling depression. The two are finally brought to Harrenhal and are put under the watchful eye of Roose Bolton. While soaking in a warm bath, Jaime confesses to Brienne about his murder of the previous King, Aerys Targaryen and his plot to burn King's Landing to the ground before Robert Baratheon and Ned Stark could take the city and how he had ordered Jaime to bring him his father's head to prove his loyalty. Jaime murdered Aerys to save millions of lives in King's Landing, but was condemned by the Starks for his "murder" of the Mad King and forever be forced to bear the name "Kingslayer".
Sansa Stark becomes friendly with the future Queen, Margaery Tyrell. Margaery tells Sansa that she wants her to truly become a sister and tells the Stark captive that she wants Sansa to marry her brother, the handsome (albeit homosexual) heir to Highgarden, Loras Tyrell. When word of this plot reaches the Lannisters, however, Tywin quashes it by insisting that Loras be betrothed to Cersei (much to her misery) and that Tyrion would marry Sansa, which inadvertently drives a wedge between Tyrion and his lover Shae. Sansa and Tyrion are awkwardly wed, though Tyrion defends Sansa's honor from Joffrey and his cruel jokes by drunkenly threatening the King in public and promising Sansa that they would not consumate their marriage until she was ready to share a bed with him, willing to take the humiliation this would bring him from court.
On Dragonstone, Stannis Baratheon broods over his defeat and the continued war efforts by the Lannisters, Tyrells and Starks. Despite the fierce loyalties of his Hand, Ser Davos Seaworth the Onion Knight and his own daughter Princess Shireen Baratheon, Stannis remains devoted to the Fire Priestess Melisandre, who continues to claim that she can see Stannis's victory over darkness in the fires. To prove this to Stannis, Melisandre sets sail for the main land to find one of the deceased Robert Baratheon's bastard children to use for a Blood Magic Ritual. This ultimately leads her to find Gendry among the Brotherhood Without Banners. Melisandre pays the Brotherhood handsomely for Gendry and leaves with him as her "prisoner", which draws her ire from Arya. Melisandre reveals to Gendry his father's identity and how he could save the kingdom and avenge his father by helping Stannis become king. After seducing Gendry, Melisandre places leeches on him to draw his blood for a spell that would ensure the demise of all Stannis's enemies. Stannis throws the leeches in the fire and declares three names: Joffrey Baratheon, Balon Greyjoy and Robb Stark.
Robb eats a significant amount of humble pie by accepting all of Walder Frey's terms for a renewal of their alliance, including a public apology for breaking his oath to marry one of his daughters as well as compelling his uncle, Lord Edmure Tully, to marry a Frey daughter in his stead. With the Frey's help, Robb hopes to conquer the Westerlands and break the myth of Lannister power by taking Tywin Lannister's seat of power in Casterly Rock. While on their way to the Frey stronghold of the Twins, Talisa informs Robb that she is pregnant with their child.
Roose Bolton informs Jaime of what has befallen the Starks and Lannisters since his imprisonment, including the Battle of Blackwater Bay and how Edmure Tully was to marry a Frey daughter. Roose further informs Jaime that he would be continuing on his way to King's Landing, provided he inform his father that he played no part in the removal of his hand. He then tells Brienne that she was a traitor and would answer for both her and Catelyn Stark's crimes as he departs for the Twins to be at the wedding. Jaime at first leaves Brienne behind, but has a change of heart and returns to Harrenhal to save Brienne and bring her to King's Landing to be properly awarded for bringing him to the capital safe and sound. When Locke protests, Jaime tells Locke he would have to kill him if he wanted to stop him, thus prompting the thug to free Brienne. Jaime finally makes it back to King's Landing, but is not received well by any present, especially Cersei, who views him as less of a man than he had been when he left.
While on her way to another slave city in Yunkai, Daenerys finds it well defended by a force of sellswords called The Second Sons. Despite respecting her titles, the Second Sons treat Daenerys coldly and warn her that if she fails to disperse and leave, it will come to war. However, one of the leaders of the Second Sons becomes smitten with Daenerys and decides to slay the others and join her ranks. Intrigued by him, Daenerys names Daario Nahaaris to her inner circle and sends him, Jorah Mormont and her Unsullied Commander named "Greyworm" into Yunkai to take the capital and free the slaves captive within. After they prove successful, Daenerys gives the slaves the chance to leave into freedom on their own. Believing her to be a benevolent savior, the slaves choose to follow her, giving her the name "Mhysa" which translates to "Mother".
Despite his love for Ygritte and his growing affection for the Free Folk as a whole, Jon is compelled to betray them when they tell him to murder an old man in cold blood. Jon escapes them to return to Castle Black and warn his brother, but receives several arrows in his leg in the process from an angry and brokenhearted Ygritte.
Robb's arrival at the Twins is surprisingly well received by Walder Frey, who seems eager to put Robb's betrayal behind them and continue on with the wedding. Despite the Frey women being known to be ghastly to look at, Edmure's bride is quite beautiful and wedding reception goes remarkably well. Everyone has a wonderful time and Edmure and his wife seem to be deeply in love. As the bride and groom are led away for the traditional bedding ceremony, however, the Frey men betray the Starks and Tullys and begin to slaughter them. Talisa is violently stabbed by the Freys where her unborn child was and Robb is skewered by arrows. Roose Bolton reveals himself to be a traitor and delivers Robb the killing blow, effectively ending the War for Northern Independence. Unable to bear the fact that she lost all her children, Catelyn Stark lets out a haunting scream as she has her throat slit.
Fed up with the disloyal and treacherous dealings of the Brotherhood, Arya escapes their custody, only to be abducted by the Hound, who had been tailing the group for some time. He plans to sell her off to Robb and Catelyn, but the two arrive just in time to witness the slaughter of the Stark forces as well as the death of Robb's direwolf, Grey Wind. Hoping to keep Arya from the same fate, the Hound knocks her out and rides away with her. With little options left, Arya and the Hound set off for the Vale of Arryn to bring Arya to her Aunt Lysa, but not before both the Hound and Arya kill Lannister Soldiers celebrating the deaths of Robb and Catelyn.
The Lannisters also revel in the death of Robb Stark, but it is clear that their loyalties and ideas of unity are vastly different. Tywin is revealed to have orchestrated the betrayal with the help of Walder Frey and Roose Bolton, both of whom have been amply rewarded with titles, lordships and castles to call their own, with the Boltons replacing the Starks as Wardens of the North and the Freys taking the ancestral Tully Castle of Riverrun, though he finds that his own children are at each other's throats and Tyrion in particular seeming to pity the Stark dead. After being challenged by Joffrey, Tywin also realizes his grandson needs to be fully reined in before they can truly declare him a King. As Tyrion tries and fails to comfort Sansa over the death of her brother and mother, Cersei suggests Tyrion give her a child to love, telling her brother that Joffrey was the only thing that kept her alive during her time as Robert's Queen.
With the death of Robb, Stannis Baratheon is convinced that Melisandre worked her magic the same way she did to help murder Renly, but Davos Seaworth remains unconvinced that they should sacrifice Gendry. When Stannis refuses to listen, Davos hurries for the dungeons to free Gendry and help him escape, having him row to King's Landing to blend in with the people again. Despite Stannis' fury with him for betraying him, Davos informs his King of word from Castle Black that the dead are marching on the Wall and an army of Wildlings closing in on Castle Black. Melisandre confirms this and tells Stannis that his path to the throne would cross through the North.