Yes, there is a call to Neriak and a call to Freeport. The Freeport one is called "Call of the Overlord"...I forget the name of the Neriak one off the top of my head. If you started as an evil character you should have the one from the city you started in automatically. If you betrayed from a good faction, I can only assume that there is a step in the betrayal that you haven't completed or, if changing alignments from Freeport to Neriak or vice versa, a step in the citizenship quest you haven't done.