I started the Diplomatic Immunity quest about 120 hrs ago and kinda found that I really didn't have the right stuff to complete it, so I left it go and decided to tackle it later. I restarted the quest last night and got through part of it rather well until it came to getting the key to the sewers? anyway I went all over the place looking for that blasted key. Yea I know there's supposed to be some guards with the guy that helped me get into the place and ya kill them and loot them and you get the key. Well, I found one guard and she didn't have it so I decided to go back to the original building I came from,WRONG! I went out the door to the courtyard and got hammered by everything but the kitchen sink. I did finally get back to the original building but nothing, no guards, no guy but one heck of a wizard but no key. So does this mean that I can't complete the quest or am I missing something. There are sooooooo many things to do in Skyrim I can't keep up. Can someone please stear me in the right direction.

VERY annoying quest. I managed to sneak my way in and back out again to the farthest edge of the estate but the game still wouldn't let me fast travel away (enemies nearby) and forced me to use the sewer exit. If you are on PC you can cheat the sewer gate open (in the console, click on gate, enter "unlock"). If you are not, my apologies. The people patrolling the room with the sewer gate are *supposed* to have the key.

At the time I was considering restarting the quest and bringing armor & weapons (or at least just bow & arrows) instead of using sneak and invisibility potions but I got through it.

One of the guys in the back building had the key. After I free'd the prisoner a thalmor soldier in armor came down and he had the key.

There was one guard there and after doing her/him in and looting, no key and no other guards either so I guess I'll "unlock" the gate, thank goodness for pc's. Thanks guys.

You need to read Esbern's Dossier. After that, the new guards with the trap door key enter.

Hmmm. I picked up a toon today that I hadn't played for about the same amount of time as treadhead.... I didn't have to read any of the dossiers to get the key.... It was on one of the guards - actually, now I rethink - I think both guards AND Ri-whosis (the torturer guy) had trap door keys.