The episode begins in Renly's camp; Catelyn tells Renly that Robb Stark has no interest in the Iron Throne. Renly says the Starks can have dominion over the North if they swear the same oath of fealty that Ned did. In return, Renly promises to defeat Stannis' army in the morning. Catelyn asks him again to try to negotiate a peace with Stannis. He won't hear it. He tells her to take his terms to Robb. There's a wind at the tent door and Melisandre's evil black spirit offspring comes in and stabs Renly in the back. He drops to the ground, dead. Guards rush in and, thinking Brienne did it, attack her. She fights them off and then collapses crying over his body. Catelyn tells her to leave, warning her they'll hang her. "You can't avenge him if you're dead," she says.
They take off. The next morning, Loras and the Queen try to figure out what to do. Petyr warns them Stannis and his boats are near. They don't believe Brienne was responsible. Petyr and the Queen warn Loras he can't avenge Renly if he's dead. Margaery tells Petyr she wants to be "the queen." King's Landing Cersei and Tyrion get the news. They worry about Stannis accumulating power. Cersei is still smarting over his plans to send Princess Myrcella away to be married. Cersei says the king is planning their defense; but he's not talking about what that means. Tyrion's cousin tells him they're making wildfire with a pyromancer and plan to launch it into Stannis' ships and armies. Davos tries to talk to about Stannis about what he saw Melisandre "give birth" to in the cave. Stannis doesn't want to hear it.
Stannis plans to sail to King's Landing after he's consolidated his troops. Davos worries about him bringing Melisandre with him. He mentions that some people think he's under her spell. Davos advises Stannis to shore up Renly's bannerman and head to King's Landing without Melisandre. He tells Davos to lead the attack to Back Bay. King's Landing Tyrion walks through the city and comes upon a man giving speeches to the crowd about the "rotten King." Tyrion thinks Joffrey is a lost cause. The man calls Tyrion a "demon monkey"; people think he's pulling the king's strings. Theon of Greyjoy awaits his crew. They're a rough lot. They're heading to the Stony Shore to rape and pillage and they're not inclined to listen to Theon. One man stares him down, saying he doesn't need a captain. Theon threatens to hunt him down for treason.
His sister comes by to taunt him for his pathetic crew and assignment. She has 30 ships. The first mate tells him he'll have to earn their respect. Theon decides to take Stony Shore, which the Starks hold, and then hold it until they arrive to fight them off. Harrenhal Arya waits on Tywin and his men as they talk about how Robb Stark, her brother, continues to outperform their expectations. Twyin asks Arya where she's from, and then questions her on the sigil. She makes up a new lie when he catches that one. He asks what they say about Robb Stark in the north. She says they say he rides into battle on a dire wolf and can't be killed. He asks if she believes that. "No, my lord, anyone can be killed," she says. She goes to get water but is intercepted by Jaqen H'gharone, one of the prisoners she saved from the fire. He says he always knew she was a girl.
He seems menacing, but tells her a man pays his debts. They stole three deaths from the Red God when she saved him and his fellow prisoners and he says they have to pay them back. She can name anyone and he'll kill them. She names the torturer. Jorah, Jon Snow, the Night's Watch trek across the wintry expanse. Sam goes on about Gilly. There's nothing but snowy mountains as far as they can see. They see a group approaching. Tyrion examines a bowl of wildfire -- it burns so hot is burns wood, steel and flesh. Bron worries about his own fighters handling it and flinging it accurately. The Pyromancer shows them his stash. It fills a vast room. They have 7,811 jars -- at Cersei's order. Bron thinks it's a "s---" idea. Tyrion agrees the contents of the room could destroy King's Langing. "You won't be making wildfire for my sister anymore; you'll be making it for me," Tyrion says.
In Qarth, Daenerys teaches her baby dragon how to scorch his own food. She wears a fancy gown given to her by Xaro, supposedly the richest man in Quarth, and the one who vouched for them. She suggests her handmaiden flirt up the other men to find out more about him. At a garden party hosted by Xaro, she has to tell her men not to steal the ornamentation. A man greets her on behalf of the warlocks of Qarth and invites her to a reception at the House of the Undying. A woman with her face obscured warns Jorah that Daenerys will need protecting. On the road, Brienne insists it was Stannis who killed Renly, but Catelyn thought it was a "shadow in the shape of a man." They're riding to Robb's camp to tell him what they saw, then Catelyn plans to return to Winterfell.
Brienne offers to serve Catelyn, whom she says has "a woman's kind of courage." But she wants permission to kill Stannis when the time comes. Catelyn agrees. They swear vows to each other. Brann listens to requests from the villagers but they're interrupted by Ser Rodrik announcing their bannermen are under attack 40 miles away. Brann doesn't hesitate in telling Rodrik to take the men he needs to defend them. Brann tells someone that he dreamed the sea had come to Winterfell and the water flooded the castle. Ser Rodrik was one of them. The sea is hundreds of miles away. Back out in the mountains, they see an encampment of Wildlings in the distance. They make plans for a sneak attack. Jon snow wants in on it and Sam offers to take his steward duties while Jon's gone. In Qarth, Xaro asks Daenerys how long Jorah has been in love with her.
She denies it. She tells Xaro she wants to retake the Iron throne and protect her people. She asks him why he let her in. He takes her down to an impenetrable vault door. He has the only key and offers her half of what's inside if she marries him. He promises to help her retake the seven kingdoms and tells her Robert Baratheon is dead. Daenerys talks it over with Jorah, who's against it. He says he just wants to see her on the Iron Throne because she'd be a good ruler. He tells her to get one ship and sail to Westeros to make allies. He promises to find the ship and captain. In Harrenhal, Gendry is back to making swords. Arya watches, giving him the same fighting advice her father gave her. They hear a scream and run to inspect. The chief torturer is dead in the courtyard of a broken neck. Jaqen H'gharone looks down from above, catching Arya's eye. She approves. The episode ends at this point.