Celaena and Sam are no longer in debt of Arobynn. But in order to be completely free, they have to pay off their dues to the Assassin's Guild. But Arobynn is a shrewd man who names a price that wipes up their total savings. So the duo take up a final job where they are betrayed. 
 This is the final installment of the series of novellas that lead up to Throne of Glass. I enjoyed read all of them, but mostly this one as this incident was a turning point in Celaena's life and leaves a huge influence on her.