You begin this level alone in a cell and without a weapon. Jump on the window ledge to set the alarm off. A guard will run into the cell. Run past the guard and open the first cell to your left as you exit. The inmate inside the cell will come out to take care of the guard. Enter the open cell on the other side of the walkway, push the box to the end and go through the crawlspace. Move the boxes all the way to the end. You may move the box again to retrieve a secret. Crawl back through the crawl space and jump up through the hole in the ceiling to the area above. Follow the hall, being sure to jump over the barbwire along the way. At the end of the hall is a switch that opens a trap door behind you. Don't jump down because it's too far for Lara to fall - and there's a nasty surprise at the bottom if you do. Climb down the ladder and through the dark passage to the trap door. Drop down, but be sure not to let the guard see you. Run into the security room and pull the switch that opens the gate. Now, the prisoners will come and take care of the guard for you. Pick-up the keycard that the guard left on the floor and use it to open the other gate. Down the hall and to the left is a door. Push the button and enter the washroom area. Go through the next door and maneuver the box around the pillar to the hole in the ceiling. Climb up to the upper level and find the switch to fill the lower level with water. Jump in the water. A trap door will open on the other side of the room. Once you've swam over to the trap door and out of the water, be cautious not to jump down into the kitchen or you will get burned. Jump over the hole and go to the right. Go down the hall and to the outside passage, be sure to jump over the barbwire at the end. Drop to the lower level to push the switch that turns off the stove in the kitchen. Return to the kitchen, and go through the doorway and through the next door on the left. There you will find the switch to open the gate to the ventilation fans. A guard will try to stop you. Walk between the ventilation fans and slide down the slope backwards, grabbing the ledge. Drop to the ledge on your left and through the crawl space to the ladder; climb up the ladder to the grid above you. The trap door will fall open, then climb up to the area above. Climb the grate and pick-up medi-pack. At the top of the hall a guard will attack you from the dark hallway on your left. Run away from him, and he will follow. Run around the corner to the left, but don't go toward the trip lasers. Drop down the number of platforms to the bottom and release the prisoner, so that he can take care of the guard for you. Retrieve the key from the disposed guard and go back to where you first met up with him. Insert the card in the slot next to the door, enter the room and turn the switch on. Now go past where the trip lasers were, climb down the ladder and go to the outside exercise area. Get the guards attention and let him chase you down the hallway (the one that was on your left when you entered the outside exercise area). Release the prisoners and let them handle the situation. Once your problem has been taken care of, pick-up the yellow security card and return to the outside exercise area. Use the key in the door on the far side. Go down the hall; take the crawl space on your right and sneak past the guard to pull the switch on the pillar. Before entering the passage, be sure to jump over the laser that is protecting the entrance. Go through the corridor, and make sure your health is full or high enough to drop down to the lower level. Once you're at the bottom, go around to the ladder, climb up and be sure not to disturb the MP. Go and get your yellow security card. Go back to the red corner and drop down, but don't go to the metal door. Instead, use the yellow security card. Climb the ladder and drop to the platform beside the water. Don't swim around - just go down the hole and pick up the save crystal. Follow the hallway, pull the switch, and surface to open the door, but be sure not to surface where the electric lasers are located. From the platform, jump over the lasers and swim through the underwater passage. When you surface in the cargo area, climb the boxes on your left and enter the door to find your weapon and some ammo. Now it's time for some action! When you leave the room watch for the trip lasers in the entrance. Once back in the cargo area, shoot the guard and make your way up the hall next to the conveyor belt. Dispose of the guards and pick up the blue card on the guard. Find the ladder on the wall; climb it and then insert the blue card in its place. Enter the doorway and pull the switch to the right. The other switch releases more guards. Back in the cargo area, use the box to climb up to the walkway above. Now monkey swing across the ceiling to the ledge, jump up to the upper ledge on the second floor and shoot the MP. Pick up the yellow security card then go back down the ladder to do a monkey swing across. Insert the card in its place and enter the passage. Then at that point you should see the truck. Go and hop in the back of it and the level will end.