The action takes place right after Rick was taken by some strange group of people. Struggling to get away from them to get back to the love of his life Mischonn (forget Lori we got to work out the quota) and killing the walkers is the second scene we got here.
Soon we discover this was just the first challenge on his official becoming of the special evil organisation , CRM's citizen.
What is happening next?
Rick can't sleep; He is constantly daydreaming about returning to Mischon (why?) More than he wants to eat, sleep and breath! What a nonsense! Despite of his several attempts to get free from the evil people that were giving him the shelter and food (they are still evil, why? Just because. John Lock from Lost just got back to his role literally!)
That's all. Later everything is just stiff combination of scenes where Rick wants to stay and Mischone trying to pull him back from them. Nah. And killing more innocent people on their way. But who counts? I mean care. Exactly.