The watchers on the wall are forced to defend Castle Black on this Game of Thrones episode.

Wildings encamped on the south side of the wall grow testy as they await their signal. Ygritte has words with Tormund when she prefers to not hear his story. Styr chimes in and questions her feelings for Jon Snow. In the background Gilly sneaks by with baby Sam in her arms.

Atop the wall Jon and Sam look out. Sam probes Jon for details about Ygritte and questions their vows. Jon tells Sam to go down below, where he busies himself reading about wildings. He is joined by Maester Aemon who talks about a love in his life long ago. Sam hears Gilly at the gate and lets her in. Their reunion is cut short though when he must answer the blast of the horn. He promises her he will not die.

Atop the wall, Alliser Thorne admits Jon's plan to seal the gate was the right move. The attack begins as wildings and giants riding mammoths make their way toward the wall. A second horn sounds, indicating that the south gate is under attack. Thorne goes to join the fight and leaves Janos Slynt in charge. He quickly shows his weakness, but Grenn fabricates a need for him elsewhere. Jon Snow takes control of the wall and issues orders.

As giants prepare to tear down the gate, Jon sends Grenn to hold it. Thorne rallies his men as they face off against the Thenns who have entered the courtyard. Olly, the young boy in charge of the lift freezes when he sees the thenn who vowed to eat his parents. Sam spots him and tells him to take up arms. Sam tells Jon they need more men in the courtyard. He goes to join the fight and asks Sam to unlock Ghost.

Jon defeats the Thenn leader Styr only to come face to face with Ygritte who aims her arrow at him. She hesitates though and is shot herself by young Olly. Ygritte who dies in Jon's arms. Back on the wall, Edd now in charge, orders the men to release a giant scythe that knocks off the climbing wildings. They retreat for the night back into the woods.

The next morning the men assess the damage. Jon tells Sam of his plan to go beyond the wall to kill Mance.