The apartment 22 is inhabited by two people, and they will attack Jensen if the main character is detected by them. Those characters can be either incapacitated or killed, or you can complete all the actions in the apartment without getting caught.
You have to take care of the computer. It has a level three security, but in the apartment you can find a palmtop with a password DobraNoc for the computer (it is on a small wooden table). Once you get access to the system, read the first email concerning the drug, which will give you the address of a different apartment in Hlavni 33 apartment block.
Important note – The description above tells about the first possible opportunity to unlock this quest after reaching Prague. You can skip this step, and unlock it, for example, after you find the palmtop in Hlavni 33 apartments, after you visit the rave, or once you investigate the apartment in Libuse apartments. In this case, you will miss an opportunity to gain additional experience points. If you want to finish this quest as soon as possible, you can visit the southern Prague canals straight away, and reach the neon laboratory with the intent to sabotage its further production.