In Game of Thrones, Winterfell is taken over by Theon Greyjoy and his skeleton crew, the city is later besieged by House Bolton, Theon is knocked out by his crew and handed over to the bastard Ramsay. This much I know. But what happens to Theon's crew after this?
According to the GoT Wiki they were flayed alive by Ramsay's men.
However, the castle is sacked by Ramsay afterwards and instead of letting the ironborn walk free, he flays them alive.
To say the truth I don't remember that being explained in the TV show. Perhaps this is based on the events from the books, where he also killed the crew, but the events there where different.
Edit: Turns out that there is a scene where Roose Bolton and Walder Frey are discussing the ironborn fate. Thanks Will Feldman!