When you in the lab and cant get the prisms do this. next to the giant laser
there's a tall box.. big enough to fit in it. jump up on top of that. There 
is a poll right above it. Climb onto that then go all the way over to the 
elevated part..(the part with computers and stuff) the jump down. There is a
computer all on its own in the corner. Hack it. Then the gun turret turns off.
Run down the stairs and grab the prisims. Then that dude will start coming 
towards the lab so run over to the lase and put the prisms into it. 
The run over to that bix tall box thing and run into it.. the door will shit..
stay in there until you know youre ready to come out (after the badies are 
inside the lab. Jump out of the box and beat the 2 dudes up and then save the
other dude.. then use the laser to blow up the things on the wall near the 
tin shutter thing.. (there's one outside and one inside) Then put the toxic 
stuff into the fuel cell and make your way outa there.