Quantum of Solace Walkthrough

Now you're inside and it sounds like some catwalking will be in order. First dispose of this guard and take his CR-1911 .45. To the right of where he stood is the camera patch for this level, and to the left...

Downstairs you'll come across two guards having a chat. You can let them finish or ambush, up to you, but you need to get in there and open bust into the catwalks. I never did manage to eliminate them both without triggering an elite squad, but at least the amount of extra guys is finite. The sooner you can grab the Mantis one of the guards dropped, the better.

The catwalk fight is pretty annoying due to all of the railings. It's really hard to get a straight shot. Maintain as much cover as possible while trying to finagle your reticule around. The other main point is to just be aware of the parallel nature of the catwalk system; enemies will come down both sides. At the end, make sure to kill the two guards on the other side of the next set of doors.