Depending on whether you killed Dahlia or not you either get "we needed her dead" OR "hard work but it had to happen". If you complain, you're told "leave the ethics to us". You're also told that this is now a fifth freedom situation - all means are acceptable.

Get in the back left corner of the elevator. Take out the light, and as you are attacked, shoot the 2 guards. Then creep forward. There's a third guard through the arch to the left.

Go left down stairs wait at the corner. Wait for the lead guard to go forward then shoot the remaining guard. Now go under the stairs and get the guard there.

Go forward and four guards will come at you. You're in a big water room here. Take them out one by one. Go forward and left into a storage area. There is lots of ammo in here, grenades too. There's also a health kit in the corner.

OK, now go back to the big room and then to the opposite wall - you'll find the lab. Three guards come in at you. Note that these rooms all interconnect - you can also get there by going forward and right from the ammo room. In any case, slay the guards. Go over to the microscope on the right side of the lab.

CHECKPOINT

You now have the biological weapon. Bellagio Sampler is waiting for you to examine it. Note that the route to the right from the big crosswalk area just goes around the back of the lab. Go out to the new elevator - and you come up to an alley with lights.

NOTE: If you didn't kill Dahlia, she is here sniping you with 3 friends. They are tough! It might be worth it to just kill her at the beginning of this area so you don't have to deal with the snipers. If you DO kill her, you get a guard that comes across the entrance of the alley. Knock him out and drop him in the dark. Make a noise and lure a second guard in.

Now go along beneath the wooden catwalk. Another guard is across the way and a fourth guard comes in. Take them both out.

Get across to the alley - "get out of there". They think a smallpox attack is the Springfield Demonstration. They can't tell you yet why you had to kill Dahlia. mission complete.

If you have to deal with Dahlia and her snipers - shoot out the hallways lights. Look up at high level white square - 2 people up there. Shoot them both. Go right and along under the wooden supports. Look across the courtyard - a third guy is up by the upper window on opposite wall (the wall with no lights on the top floor). The fourth sniper is straight ahead when the exit is up to your left.

Splinter Cell Pandora Tomorrow Walkthrough