Ramsay the Bastard of Bolton has sent Theon, of all people, into Moat Cailin to secure the surrender of the Ironmen troops there. I'm surprised Theon is functional enough to do the job.
But Theon who thinks he is Reek does manage to persuade the men that he is really Theon, and the Ironmen are all half-dead or drunk by this point anyway, and aware that they have been abandoned by Victarion after the kingsmoot did not go his way. Presumably a similar situation awaits Stannis, or the Boltons (whoever gets there first) at Deepwood Motte. Theon manages to walk away with all the men (an axe in the head of the one who did not want to surrender helped).
Theon is grateful to to Ramsay for letting him keep his remaining fingers and is allowed to eat and sleep with the dogs, which is quite an upgrade from the dungeon. The surrendering ironmen are all killed, natch.
Ramsay's dad Roose turns up with a new step-mother for Ramsay (a Frey woman) and his bride, fake Arya, who Theon recognises as Sansa's rather sill friend Jeyne Poole. Did we know it was Jeyne? Not sure. But anyway: poor Jeyne! Will Theon say anything about this? Is it possible that he and Jeyne will end up helping each other?