I am doing the quest called "BLINDSIGHTED" I am at the part were i have a final confrontation with Mercer Frey in Irkngthand. When i enter the door with Karliah and Brynjolf my character goes to the edge of the ledge and i am unable to move but i can look around, Karliah and Brynjolf are standing near the door we came in from. They talk a moment aand Karliah says for him to climb down, then Mercers voice come in saying Karliah could never best him.

After he says that there is nothing they just stand in there spots doing nothing and i am frozen in my same spot. the only thing i can do at that point is load a older save and try coming in again, I have done this about 20 times.