On the police radio, you hear an announcement concerning shots fired at a warehouse owned by your old friend, Vladimir. Upon arrival, you hear additional shots from the upper floor, along with what appears to be a hostage situation. You call for backup, but the cops are still one chapter away.
The warehouse had an entrance
Check the cleaner's vans - they will contain an extra pistol, and ammo. Next, enter by the side door, reached by going to the right of the building. Within the first room, you will see a small cutscene where you hear a telelvision playing a TV show. Continue to the back corner, where you will encounter a janitor. He will unlock a few doors for you. In the third room, the action starts - the cleaner will attack you from behind, while the other cleaner approaches from within the room, behind the blood stains.
The next room has two cleaners in the middle, easily ambushed in a few quick shots. The next room leads to a staircase, where two enemies are unaware of your presence, and can still be ambushed. You can also find an answering machine, which contains a message from Vlademir.
Enter the door, and take the first door to the right. You should be approaching the hostage, see a cutscene with the two cleaners and her. One cleaner has an Ingram MAC, while the other has a pistol. The action will also pickup, with enemies being alert and approaching with better weapons.
Return to the main hall, and take a right. After fighting a few more cleaners, you will meet Mona as she leaves on the fright elevator. Take the elevator she just used, and head to the ground floor. The cleaners mention heading out the back to avoid the cops. Proceed to the back of the warehouse, where there are only a few enemies left. Once you reach the alley, you will complete the chapter.