One of the key recurring themes in Game of Thrones is that you need to be careful of what you ask for. This is made most evident in the perilous circumstances of the Stark children. Arya Stark didn't want to lead the life traditionally proscribed for girls and ladies. She wanted to do what the boys did. Well in a way she got her wish. She was running for her life with a bunch of male desperadoes and refugees until she was captured. She's seen a ton of violence and had to do some killing. Sansa Stark wanted to be betrothed to a king. Well she is but unfortunately the king is a capricious sadist who delights in causing her emotional pain as much as he does physical. Robb Stark wanted to be a great leader, like his father Ned. Well now he's learning that war is no game and there aren't any easy or good decisions in war, only less bad ones.
This episode opened with two hapless Lannister soldiers meeting the business end of Grey Wind, Robb Stark's direwolf. It's not really explained well but Grey Wind has found a secret path that allows the Stark forces to flank and surprise the Lannisters. Shortly afterwards Robb has won another battle and killed five Lannister troops for every Northern man lost. Despite this Robb still has a chivalric (and perhaps unrealistic??) idea about war. We get to see the introduction of another Stark bannerman, the enigmatic and ruthless Lord Bolton, who urges Robb to allow torture of captured troops for information, a suggestion Robb angrily dismisses. Bolton is also not happy about using Northern forces to guard prisoners. There is the explicit introduction of some modern ideas about the pointlessness of war, put in the mouth of an attractive nurse. Robb can't debate the right and wrong of war but he likes how the nurse looks.
News of the latest Lannister defeat reaches King's Landing. Joffrey decides to take out his frustrations by having his bodyguards publicly beat and strip Sansa Stark. The court is shocked but no one does anything until an angered Tyrion intervenes. Joffrey and his kingsguard are of course bullies and have no stomach for standing up to Tyrion. Punching and humiliating teen girls is more their speed. Sansa Stark is too frightened to respond to Tyrion's kindness with anything other than repeating canned lines about her brother's treachery. In order to try to remove some of Joffrey's negative energy Tyrion sets him up with two prostitutes but this ends badly as Joffrey really is more interested in beating and hurting women than he is in physically bonding with women.
Cersei sends Lancel Lannister to insult Tyrion and bogart him into releasing her spy, Pycelle. Tyrion very quickly picks up on the fact that his cousin really has no business seeing Cersei at this time of the night unless they are bumping uglies, something which Lancel shamefully admits to. Given that neither Tywin nor especially Joffrey would be happy about this, Tyrion blackmails Lancel into becoming his spy. Tyrion knows how the game is played. Peter Dinklage owns this character.
Littlefinger visits the Renly camp and butters up the arrogant Renly beautifully. He also makes a play for Renly's wife Margaery (basically saying if you need a real man call Littlefinger) but she shoots him down in a quiet yet cutting manner. He then visits Catelyn and urges the release of Jaime Lannister in return for Catelyn's daughters. Littlefinger has returned Ned's remains (not shown directly). Michelle Fairley really shines in this scene. She is just so believable as Catelyn. This was the most powerful acting in the episode, I thought.
One of Danerys' riders has found the city of Qarth-a merchant city ruled by the Thirteen. The Qarth rulers will let her and her starving people in but only if she shows the dragons, something she doesn't want to do. I liked the wordplay in this scene. She is allowed in when one of the Thirteen merchants, Xaros, decides to vouch for her.
Arya Stark and all of her group that weren't killed last week are now prisoners of the most sadistic Lannister bannerman, The Mountain. As much for fun as for any other reason, The Mountain's men are torturing and killing a different person each day. This situation is utterly hopeless. These people are literally like chickens in a coop. Every day a different one has its neck wrung. We get to see the beginning of Arya's prayer, where to get to sleep, she intones the names of people she intends to kill. Nice. Just as Gendry is about to be taken and tortured, Tywin Lannister arrives at Harrenhal and puts an end to the torture, not for any sort of moral reason, but because he thinks it's a waste of manpower to have so many of his troops standing around guarding/torturing people. He has a war to fight. It's also better to have prisoners working for him instead of dead. It is interesting that both Tywin and Tyrion stop atrocities under their watch for slightly different reasons. Tywin recognizes that Arya is female and takes her for his cupbearer.
There is a showdown between the Barratheon brothers. Both actors raise their game a bit here. Stannis has no doubts that he is the rightful king while Renly has no doubts that he would be the better king. Catelyn Stark again tries to get them to put aside their quarrel and join the Starks against the Lannisters but to no avail. Don't get in the middle of a family fight is good advice in our world and also evidently in Westeros. Stannis gives Renly a day to come to his senses. Evidently Renly didn't do so because at night Stannis sends Davos with Melisandre on a secret mission where Davos must smuggle Melisandre near Renly's camp. I believe the actress playing Melisandre (Carice Van Houten) is using her own (Dutch) accent here. It sounds exotic. Melisandre is very well aware of the erotic impact she has on men. She makes Davos nervous as much for sexual as for religious or supernatural reasons. Anyway she strips and is quite pregnant. In fact she's ready to deliver. Something comes out of her -something shadowy, wraithlike and not remotely human.