Chapter Four: Dearest of All My Friends
You must protect Vinnie. He'll hide from guards but you must keep him alive to complete the task. He's a pretty big target in that ridiculous suit! While he hides in the office, kill the commandos that enter. He'll walk out and hide again as more enemies pour over the wall. You can intercept them outside by exiting to the right. After you hear a car pull up, hop through the window using the ramp. Attack the incoming enemies from this position. Watch out for the window to the right as an enemy could sneak in. When you're done, Vinnie will move on.
He'll stop in the next room as guards enter from the window to the upper left. Blast them as the round the crates to the left of the window. As Vinnie moves to the next door, search the locker for painkillers. He can't fit through the door so he'll start back to an elevator. Watch to the left then behind him for a few more attackers.
Snag some painkillers to the left. Vinnie will move into the elevator but you shouldn't follow. Instead, go up a flight of stairs to the left and wait for the guards to enter from the door on the opposite site. Start blasting as they enter. Watch the door to the right also. Go to the top of the stairs to rendezvous with Vinnie and enter his apartment.
Search the cabinet quickly if you need painkillers. Face the front door and blast anyone who enters. Vinnie hides again (he's a collector!). Go to the balcony and wait for the enemies to enter. Peer over the side and eliminate the enemies below. Allow Vinnie to drop while you remain high; a van pulls in, releasing some commandos. You can hit them easier from the high vantage point. Drop down once they've perished and follow Vinnie.
Proceed around the corner and move to the left. Another van pulls up as Vinnie attempts to open a door. Kill the enemies (the first is higher on a ledge to the left). After eliminating that group, a secondary squad climbs over the wall behind the van. Vinnie enters the bay door. Collect ammo then enter through the adjacent door. Go up the stairs and use the control pad to lift Vinnie.
While he lifts, a van busts into the garage. Hop down the stairs and annihilate the commandos as they try to pile out of the back of the van. There are some painkillers on a top shelf (you can shoot the boxes they're on to knock them down). Follow Vinnie back up the stairs.
As Vinnie is approaching his getaway van, turn around and face the route you came from to kill a few more pursuing commandos. Walk back to the van to complete the chapter.
Chapter Five: A Losing Game
You once again assume the role of Mona. Go left and down the stairs. Jump through the hole to the left and turn right. Go into the next room. Stand away from the barrels and gas cans; they're about to explode. The wall opens to the left so run through at the earliest opportunity. Around the corner, wait for the explosions and run up the beam and drop off to the right. Hop off the structure beyond the flames on the right. Run through the insane asylum lobby to the opening to the right.
Go right and avoid the rolling object. Grab the painkillers from the cabinet and use the fire alarm to douse the area with water. Go left and enter the door to the left. Keep going until you reach the open fuse box. Hit the button. Return to the power section (the electricity was blocking the stairs) and ascend. Move forward until a cut scene interrupts the action. Ascend the staircase in the far left corner. At the top, you'll find Max.
Chapter Six: There Are No Happy Endings
Talk to the cop. Enter the door on the left to find the body. Now you're in the police station. Go into the lineup room. Exit to the left then to the right and follow the hall. Talk to the cleaner if you want and continue to follow yourself down the hallway. Follow the only available route into a door on the right at the far end of the hall. Reach the three doors. Go forward and find the mirror (freeze!). Go left and then to the right and find Mona.