Splinter Cell: Chaos Theory

All missions:
Hold L + R at the main menu and press X(5), Y(5). A sound will confirm correct code entry. All co-op missions will be unlocked. Note: The same code also works for regular missions. After signing into your profile, on the menu screen hold L + R and press X(5), Y(5).
Austin.

Movie trailer:
Complete the Lighthouse mission in solo mode.

Elite difficulty:
Successfully complete Story mode.

Hint: Keypad codes:
adtg teft, BiG_FaT_SpErM, Brian Simonette.

Mission 1: Lighthouse
No keypad locked doors

Mission 2: Cargo Ship
No keypad locked doors

Mission 3: Bank
Keypad to left security booth on first floor: 3624
Keypad to right security booth on first floor: 3624
Keypad to main security room: 2306
Keypad to treasurer's office: 8645
Keypad to bank's back door: 3901
Keypad before president's office: 3490
Keypad to safe in president's office: Code unknown, must be hacked

Mission 4: Penthouse
Keypad To Dvorak Room: 0280

Mission 5: Displace
Keypad to door between meeting room and lobby on second floor: 8136
Keypad to door between meeting room and lobby on first floor: 8136
Keypad to CEO's meeting room: 2346
Keypad to CEO's office: 2609
Keypad to fire escape: 3485
Keypad to central server room: Code 2109
Keypad to R&D server room: 9205

Mission 6: Hokkaido
No keypad locked doors

Mission 7: Battery
Keypad to shipping area: 1879
Keypad to elevator: Code unknown, must be hacked

Mission 8: Seoul
No keypad locked doors

Mission 9: Bathhouse
Keypad to owner's office: 3650

Mission 10: Kokubo Sosho
Keypad To Server Room: 1945

Hint: Catching Shetland:
Have your sniper zoomed-in on the guard. When there is a fight, shoot, run, and catch Shetland. Then, end the mission.
thomas.

Hint: Aquarius: Killer area:
Go to the pirate room, then go to the left. Go to the little hallway to the Techroom. When you are on your way (if you are still in the hallway) look to one of the sides to find a little box area. Crouch into it. If someone presses the button on the outside, the area will be closed and you will not be able to get out. If you stay there too long, the area will fill up with water and you will die. The only way to stay alive is if someone presses the button again and the water drains out.
BamSk8rkid.

Hint: Bank: Invisible laser beam:
To avoid detection by the invisible laser trip wire in the entrance of the vault, closely examine the entrance with your thermal goggles on. Then, use your OCP to disable the laser emitter and walk out of the vault. By doing this, you can leave without sounding the alarm.
ODST29.

There is an invisible laser at the entrance to the bank vault. Before you go down, take a guard down with you and into the vault. When you leave, just pick him up and walk out and the alarm will not go off.
Cyril Peart.

Hint: Bank: Do not trigger the alarm:
Normally when you are on the last part of the bank level and take the $50,000,000 from the cell, when you walk out you will trigger the alarm. There are three ways to avoid this. The first is to eliminate every guard in the bank. When the alarm goes off, no one comes because they are either dead or knocked out. The second way is useful if your trying to get a good rating without sounding alarms. When you take the money, do not walk out. Turn on your heat vision and you can see the laser. Then, turn on your goggles to where you can see the electronics. The laser should be on your left. Use your secondary fire on your pistol and disable it. Quickly run out of the cell. For the third way, make sure there are guards remaining and before you take the money, there is a computer terminal. Open the door and turn on the sprinklers. Wait for them to turn off and the whole chamber and the path to get into the chamber will be wet all the way to the narrow hallway. Take the money and trigger the alarm. Take out your sticky shockers and wait for the group of men to stand in the puddle. Make sure you are not seen or the guards will run for cover. Then, shock them.
Mike Rechtin.

Hint: Bathhouse: Finding the bombs:
After going through the gate when chasing Shetland, the first bomb is directly to the left of the gate that you enter. Go left through a little crevice and you should see a red light flashing. Go to it and disarm it. When you do that, one of Shetland's gaurds will walk up the stairs. Kill him. To get to the second bomb, go up the stairs. Turn left then turn right and look straight ahead. You should see another red flashing light down below the walkway. Hop over the ledge of the railing and disarm the second bomb. When you are done disarming the bomb, jump on to the railing and pull yourself up. Two guards will be to your left, walking on the walkway. They will probably hear you; get ready to kill them. It is fairly difficult to kill them without losing a lot of life, or at least dying. After you kill them, go down the walkway to the back wall. About halfway you will see another red flashing light. Jump across the little gap and disarm it. A guard will come through the back door right when you disarm the bomb. Kill him, then go through the door and meet Shetland. You will then have to make a critical choice; note: pull the trigger. It would be a good idea to quicksave the game whenever you disarm and kill the guards.
Chris Tafoya.

Hint: Bathhouse: Alternate Shetland Death:
At the end of the level, Shetland and Sam will be on top of a roof with their guns pointed at each other. After a short conversation, Shetland will put his gun away and say "You wouldn't shoot an old friend". You are given a choice, shoot or put your gun away. If you shoot, Shetland will stumble backwards and the intermission sequence for the level's ending will play. However if you put your gun away, Shetland will quickly pull his gun out and point it at Sam. Sam will duck his weapon and stab Shetland in the stomach before throwing him. This will then start the same ending sequence.
helldemon47.

Hint: Bathhouse: Splinter Cell reference:
You must go through the warm baths at one point in the level. There are two guards here. Interrogate one of them and he will tell you that Shetland's elite guards have thermal goggles. He will also add that they will not do much good in steam, because steam is not fog, as in an abbatoir. This is a reference to the original Splinter Cell game, in which Abbatoir is a level.
weberkki.

Hint: Displace: Prince Of Persia: Warrior Within reference:
While infiltrating Displace International, Sam will encounter two guards talking about Prince Of Persia: Warrior Within. It is in the small cafe next to a laser filled hallway, past a keypad locked door. A second way to access the room is through a vent. However because Sam is inside the vent, the conversation becomes difficult to hear.
tarek naboulsi.

Hint: Hokkaido: Splinter Cell reference:
After you scan Milon Nedich's liscence plate and enter the building, you will overhear some guards talking about ninjas. One will be telling the other that he was stationed on an oil rig and that it was attacked by a ninja. This is a reference to the first Splinter Cell in which Sam is the ninja.
Morgan Zearott.

Hint: Hokkaido: Bill Gates reference:
There are two guards talking about their new vehicle. During the conversation, one says that it has a 640 gig MP3 player, "standard." The other replies that no one will ever need 640 gigs. This is a jab at a comment made by Bill Gates back in 1981 about no one ever needing more than 640 K of RAM.
Matu.

Hint: I-SDF Base: Splinter Cell reference:
You can overhear a couple of guards talking in the main hall. One will say something about how guarding the place is just like guarding the CIA HQ; nobody would break in there. This is a reference to the original Splinter Cell, in which you must break into CIA headquarters.
weberkki.

Hint: I-SDF Base: Metal Gear Solid reference:
When you get to the lower floors in the I-SDF base, interrogate a guard. Sam will ask him about his LTL (less-than-lethal) weapon. The guard will tell Sam that the ammunition is some kind of electric round. Sam asks where he can find some. To this the guard replies: "It's not like you can shake me, and make my ammo drop on the floor". This is a reference to the Metal Gear Solid games, in which you can do just that.
weberkki.

Hint: Lighthouse: Alternate way to retrieve the radio data:
During the mission you will have to overhear some data being said on a radio transmission by a guard. If you fail to do this, you can just find the data in a filing cabinet next to the radio.
Matthew020192.

Hint: Lighthouse: Get rid of the enemy on the top:
To get rid of the enemy on the top of the lighthouse, hang along the edge of the lighthouse. Get underneath him and select the command "Grab NPC". Sam Fisher will grab and throw him off the edge. From here you can watch him scream and fall to his death.
Matthew020192.

Hint: North Korea: Half-Life reference:
In the missile battery stage, at some point Sam asks Grim if he could use a crowbar to open the console in the battery. She says "That's for geeky scientists". This is a reference at the Half-Life games where you play as a scientist with a crowbar.
Kevin Halacy.

Hint: North Korea: Ronald Reagan reference:
This game was developed at about the same time that Ronald Reagen died. In the missile battery stage, a missile is launched at the USS Ronald Reagen. Grim tells you this and Sam says "You want me to win one for the Gipper?"
Kevin Halacy.

Hint: Panama: Never set off alarms:
When you are close to the part with the lasers, go down there and set off one alarm. Kill all the people. When you cross the lasers, you will not set off another alarm. You can now finish the mission without setting the alarms off when crossing the lasers.
GlitchfinderX2.

Hint: Penthouse: Bouncing guard:
On the ground floor after you have knocked out two guards (the one who is repairing the elevator and the other one that is talking to him), put one or more of the guards in the elevator with Sam. Sam must turn on his night vision and press the button to go to the top floor. Watch the guard's body bounce around like popcorn.
Matthew.

Hint: Penthouse: Merc:
Go to the part where the merc is sitting on a bed listening to rock and roll music. Kill him, then go to the glass door leading outside. Punch the glass out of the door. If you bash the door without the glass in it, you will be killed and thrown against the wall behind you.
RichiePops.

Hint: Penthouse: Ubisoft references:
In the introduction sequence for the mission, when you see a blimp, you can also see a Ubisoft logo on it.
Felipe Roriz.

When you ride the rope in the NYC sign near the helopad in the rooftop, you can see "Ubisoft" on the building you are riding to.
Felipe Roriz.

Hint: Seoul: Destroying the tank:
In the very last area of the second part of the mission, you can rescue the injured pilots as a bonus objective. However, instead of waiting for the lamp to flicker on and off to get past the tank safely, there is an easier way. Make sure you have a frag greanade (obtained elsewhere in the level). Go to the very top of the scaffolding and take out the frag grenade. Aim the grenade to go in the hatch of the tank. If done correctly, the grenade will explode in the tank, which will destroy it. You will no longer have to deal with tank gun.
chrismir2004.

Hint: Seoul: Original Splinter Cell music:
When you begin the level, you are in a child's room. Immediately exit the room and go to the right. When you reach the end of the hall, in which the walls are blown away, turn to the right and enter a half-destroyed room. There should be a radio inside. Turn it on, and it will play the same music from the cafe from where you started near the Chinese Embassy 2 level on the original Splinter Cell.

Hint: Seoul: Teddy bear:
After you exit the bedroom at the beginning of the level and go down the alley bypassing the wall mine, interrogate the two soldiers. Climb over the gate where the Mobile Command Center is located. There is a teddy bear in the far right corner next to the fire and the wall mine. They are behind a tall wooden box. You can pick the teddy bear up and throw it.
h4x0rw1z4rd.

Hint: Ledge grab:
In order to do a better ledge grab, press A, then when the spy puts his legs up on the thing he is hanging from, press Forward while tapping A.
SM.

Hint: Defeating ISDF guards:
In any mission where you must deal with an ISDF guard, you cannot knock them out with gas. Try using a shotgun.
MarineGF2004.

Hint: Sneaking:
If you move around with your gun drawn, the noise meter will not move. This is very useful when sneaking up on someone quickly.
Cody May.

Hint: Moving faster in water:
In any mission when you are in water, take your gun out. You will move faster.
SylviaCo06.

Hint: Taking lights out silently:
To take out lights silently, first OCP the light, then shoot it instantly.
Balaji.

Hint: Destroying Wall Mines:
If you encounter a Wall Mine, do not use your OCP. Instead you must destroy it. Either throw a frag grenade at it, or shoot it with a gun (pistol recommended).
Andrew Sommers.

Hint: Alternate dialogue:
If you trigger alarms, the guards will be more alert and wear helmets. When you have four alarms all secondary and opportunity objectives are cut, and the funny long dialogue is simplified. This is what happens when Otomo tries to commit seppuku. Fisher says "I think someone is taking himself a bit too seriously." Lambert then says "We can't afford to let him die, Fisher. Get in there and stabilize him. Fast!" The following occurs when you have four alarms. Lambert says "Otomo tried to commit seppuku. Get in there and stabilize him, fast." When you have four alarms in a level all the funny conversations are replaced by one person giving a monologue.
Joey.

Hint: 100% rating:
In order to get a 100% rating on any mission, you must complete the level with the following statistics. It is unknown at this time if there is a reward for getting a 100% rating on every mission.
helldemon47.

Enemies killed: 0
Civilians killed: 0
Bodies Found: 0
Times Identified as intruder: 0
Alarms sounded: 0

Hint: Rating percentages:
The following actions will subtract from your total rating percentage each time they happen. In order to get 100%, you can knock out enemies and civilians, but you cannot be detected, bodies cannot be found and you cannot trigger alarms.
Joey.

Identified as intruder: -3%
Enemies knocked out: -0%
Enemies injured: -1%
Enemies killed: -2%
Civilians knocked out: -0%
Civilians injured: -5%
Civilians killed: -25%
Bodies found: -5%
Alarms triggered: -5%

Glitch: Floating Splintercell:
When you first begin the Co-Op mode mission "The Docks", there is a sidewalk to the left with an opening (A small ramp of sorts) in front of the door. Walk up to it and move towards (Up) and on (Right) the ledge at the same time. The Splintercell will begin floating. If you hold the controller he will continue to float. Note: This may require some practice.
J. Underwood & J. Spinelli.