Soneschen
Soneschen is the man who was in charge of the wall and who didn't let both Jack and her mother to enter the wall under the excuse of them being overweight and danger to their supplies. He was the man who tried to force her father to choose between his wife and daughter, saving the one and condemning the other to death, to which her father disagreed. It is not a surprise to find the same man being in charge of the monsters, the same monsters he was in charge to protect the people inside the wall from, the raiders, and it shows just how corrupted the society's become in the world where people like that in control. The plot provides a satisfying conclusion to his story when Jack is the one who points her father's gun at him and kills him.
Dean's plot twist
Dean is Jack's lost brother, for whom she left the safety of her home in order to find him. Probably the greatest plot twist, even greater than Kevin's betrayal, is the revelation that Dean is Hastings, the man who is the head of the raiders. The scene where he is the one choosing Jack's way of death is heartbreaking, but it all culminates to the moment where Dean reveals his true intentions, the reason he joined the raiders, and that is to destroy them.
