1. Jock drops you off on the 'Ton Hotel roof, and instructs you to find Paul in his apartment.
2. Descend the nearby fire escape and enter Paul's apartment window.
3. You'll find Paul here. Talk to him repeatedly to learn what he has to say about UNATCO, Silhouette, and your parents. He tells you that proof is in a DataCube that sits on the edge of a table at NSF Headquarters, to the west. He gives you a photograph. Take the Medkit on the ground next to Paul.
4. Enter the code behind the painting and open the secret closet. Inside you'll find a lockpick and an Augmentation Upgrade Canister.
5. Exit Paul's apartment through the window and head through this now-open tunnel to the northwest.
6. Talk to the guard before heading past the barricade.
7. You'll find a Medkit hidden in this corner.
8. Paul instructs you to access that satellite dish visible above. You can either hack the dish computer system on the roof or get the code hidden in a secret hatch.
9. We're going for the hatch. Head through this door.
10. Near the garage doors you'll find this spot with a circle on the floor - the hatch. But it's not open yet.
11. Inside this crate you'll find a Hazmat Suit.
12. Grab a recharge from the bot and head up to Level 2.
13. If you've been following along, this Medkit should bring you to the maximum number you can carry, 15.
14. For some good background listen to the guards in this room talking about Walton Simons - philanthropist. They're being paid by Simons to delete evidence on the NSF mainframe.
15. Up on level three you'll find this DataCube, revealing the presence of Halon gas in the computer room.
16. Through these windows you can see the Halon gas. The Hazmat suit you just picked up will protect you from the gas.
17. But the DataCube mentioned that the gas can be vented -- here's the switch.
18. Once inside you can hack this Terminal to open the hatch on Level 1.
19. Descend through the now-open hatch on Level 1. You are awarded an Area Location Bonus of 50 skill points.
20. Through this basement door you'll find a locked door on the left, which you can ignore. (Inside is a Security Terminal controlling nothing that isn't already unlocked, plus some ammo if you aren't playing stealthy.)
21. To the right is an unlocked door leading to this boobytrapped hallway. Disable the first set of lasers with multitools on the nearby Control Panel. Proceed through the indicated crawlspace.
22. Through another unlocked door are these crates holding a lockpick and Multitool. Be careful moving the TNT crate above.
23. Through yet another unlocked door you'll find these lasers, which are not deactivated by bypassing the nearby Control Panel. Instead, stack these crates as shown here.
24. Bypass this Turret, giving you a clean run through the lasers and the door directly ahead (inset). Alternately, you could use an EMP grenade to temporarily disable the lasers.
25. Inside you'll find this hazardous gas. Behind the locked door on the right are two EMP Grenades and a Hazmat suit.
26. Through the door on the left is this corridor. Bypass the nearby Control Panel then crawl under these lasers.
27. On the left you'll find Ballistic Armor and a Medkit. Just visible on the left is a Control Panel. Bypass it to make your next step easier.
28. With the middle laser disabled, you can move the crates out of the way then just hop over the bottom laser.
29. Equip a Hazmat Suit then approach this area on the right. Inside this crate you'll find two Multitools. Directly ahead is a Control Panel which, once bypassed, disables the remaining lasers in the area.
30. Continue down the hall through this door to another NSF mainframe.
31. Pick the lock on this cabinet to get a new lockpick and two Bioelectric Cells.
32. Pick the nearby locked door and enter this room. Atop this cabinet is the DataCube revealing the dish control computer login MCOLLINS and the password REVOLUTION, plus the communication console login NAPOLEAN (same password). You earn an Accomplishment Bonus of 150 skill points.
33. Unlock the cabinet to get an Accuracy weapon mod, a Gas Grenade, a Prod Charger, and this DataCube with the evidence Paul mentioned earlier. Note: The GoTY edition places the DataCube atop one of the server machines. Details in a Gamespot forums posting here. (Thanks, Victor.)
34. Ascend these stairs back to street level.
35. Head back inside the building then go all the way up to the roof.
36. The unlocked door ahead is your objective - satellite dish control.
37. Don't miss this LAM in the corner.
38. Use the login MCOLLINS and password REVOLUTION on the computer. Make sure to press each of these buttons to properly align all the dishes and open the communications door.
39. Pass through the now-open communications door. Use the login NAPOLEON and password REVOLUTION to access the computer inside. Broadcast Paul's message to the NSF (center).
40. Paul radios news of your success, and you earn 300 skill points. Paul instructs you to meet him back at his apartment.
41. But you need to lay low. Walton Simons orders the UNATCO troops to kill you. Getting out won't be easy. You have officially switched sides from UNATCO to the NSF.
42. We're going to use speed to get out of here safely. If you haven't already used the Augmentation Upgrade we found in Paul's apartment, upgrade your Speed Enhancement to Tech Four now.
43. Activate your Speed Enhancement. Brush past this guard and exit through the door.
44. Turn right and leap over this wall. Wee!
45. Talk about a leap of faith! Follow the arrows and you'll breeze to the the next map segment before the troops have a chance to bring you down. Your Tech Four Speed Enhancement will allow you to take these drops with only minor damage.
46. Keep your Speed Enhancement active and leap right over this barricade, leaving the trooper in your dust.
47. Dash through this tunnel you strolled through before.
48. Turn down this alley as indicated.
49. Lastly, use your Speed Enhancement to jump onto the fire escape. Ascend to Paul's apartment window after deactivating your Speed Enhancement.
50. Talk to Paul. He explains that Walton Simons works for a secret organization called Majestic-12.
51. Men in Black are at the door. They order you to lay down your weapons and surrender. Paul orders you out the window, and gives you the subway gate code 6282.
52. Your capture is inevitable, but you do have choices. Exiting the apartment through the front door results in a nasty firefight. Since we're avoiding conflict, that choice is out.
53. Exiting the apartment through the window results in Paul's death. Gunther will inform you of this after you exit the subway station.
54. To keep Paul alive, you cannot exit the 'Ton Hotel through Paul's apartment window. Hide in the secret closet and Paul will defeat the MIB. There is a switch to close the closet doors for maximum safety.
55. Paul will follow you into the lobby. Be patient and allow him to thin out the troops blocking your exit.
56. Paul is invincible against the MIBs and UNATCO troops. Activate your Speed Enhancement and dash through as indicated.
57. Equip your Ballistic Armor and run to the subway entrance. There are Security Bots and UNATCO troops patrolling the street, but your speed will keep damage to a minimum.
58. Use the gate code that Paul gave you - 6282.
59. Enter the subway and Jock tells you that he has to to take off. You earn 50 skill points for making it this far. Take the subway to Battery Park.
60. Anna is waiting for you on the platform. Keep your Speed Enhancement active and rush past her after the conversation.
61. Rush up the stairs and you'll find Gunther Hermann waiting for you. Resistance really is futile; you might as well surrender to end the level.