From the preview at the end of the last episode, it looks like Carrie and Brody are doing a runner. Thanks to Carrie's inside knowledge and Brody's previous experience as a super-terrorist, they will beat the CIA and get away. In the third season, Brody will then subtly convert his newly found Bonnie over to the Islam. This extremly volatile couple will throw the US into total chaos, which is furthered by Saul exposing the CIA black-ops shenanigans.
Everbody thanks him though and he is appointed as the head of the CIA; he is the foremost expert on Carrie's mind and train of thought afterall. During the course of the season, the devilish "Carrdy" duo carries out a couple of terrorist attacks, but is tracked down by Saul eventually. In the inevitable shotout, Brody gets killed but has time to confess to Carrie how happy he is to be with Isaah again. Saul enters the room and stays there silently, pondering how it all could have come to this.
Carrie gets up, now completely out of her mind, walks towards Saul and says: "Heeeey, Saul, you know, we can fix this, you and me together". She starts fumbling around his arm, to which Saul replies: "What the fuck are you doing".
Dana storms into the room and shouts: "THE CIA DESTROYED MY FAMILIY! I HATE YOU!". She then throws a carton of sour milk at them. The end.