Enter one of the following numbers at any phone to active the corresponding cheat function. If you entered the code correctly, you will hear a message.
2K Darkling
Enter "555-4263" as a number to unlock the 2K Darkling.
Golfer Darkling
Enter "555-5664" as a number to unlock the Golfer Darkling.
Collectable phone numbers
Enter one of the following phone numbers at any phone to unlock a collectable:
Find Vinny Mortarello in the Fulton Street Station. There's an open window in an apartment building across from Shrote's building. The Construction Outfit is inside the room as well as Collectible #45.
Darkling
At any in-game phone dial 555-GAME (555-4263) you will unlock a special Darkling.
Defeating the Darkness in the castle
To defeat the Darkness in the castle (after you have blown open the gate), go up to every chair you see in the main room. Each chair will prompt you to activate it. Note: This does give away your Darkness powers for the time being. After the Darkness appears as a red/evil Jackie, put any guns away so that just your hands are out. This will stop his attacks. Then, walk up to him without any guns out, and a prompt should appear to "Accept Him". The fight will then be over.
Demo version: Popeye cartoon
In the Grinders Lane stage, go to the room with the television. Press X when you see "Switch Channel". Popeye The Sailor will start playing.
Entire in game movie: 'To kill a mocking bird'
When you are invited to Jenny's appartment early in the game, snuggle with her while watching the TV. the movie that's on is the film version of the classic novel "To kill a mocking bird". it is possible to watch this entire movie through the game.
Entire in-game movie
About three hours into the game, after you pass the cold storage part, you will end up in a hallway with a lot of doors you can open. The middle door will have some computers and an enemy that never heard the gunfight because he is watching a television with some headphones. Kill him and the television will be yours to use. The option to change the channel will be given to you. Change the channel and some music videos and cartoons will pass. Wait a few seconds to see what is coming on next. There will be one with some cheesy music and words, and white lines coming out. This is actually a movie from 1955 called The Man With The Golden Arm starring Frank Sinatra. You can watch the entire movie on this television.
When you are in Jenny's apartment, sit down with her and the film To Kill a Mockingbird will start. It is possible to watch the entire film.
Fireman Outfit
Find Jimmy the Grape in the Canal Street Station. Talk to him to activate the objective. Pete's in a nondescript apartment building down Grinder's Lane. It has a small parking lot outside. Pete's inside room 261. Break in and handle the enemys. Grab the Fireman Outfit.
Golfshirt Outfit
Dial 555-5664 at nearest train station.
Jenny in Chapter 4
When you are about to give up the Darkness guns and extract the Darkness, look at the Demon in the middle. Look behind him in the bright light and you should see Jenny.
Jungle Outfit
In Hunters Point Alley, it's inside the same room as Collectible #97.
Keeping the zombie soldiers dead
When you are in the "Otherworld" (you will go there after you die the first and second time), the Germans soldiers almost always get back up after you kill them. The only way to make sure they remain dead is to devour their hearts.
The following is an easy way to keep the zombies dead when you die. Kill them with the demon arm, and throw them off the ledge. Note: This only works outside. If you throw them off the ledge inside a building, they will not die. Instead, they will follow you up to the level you are on. You can also devour their hearts to keep them dead.
Lumberjack Outfit
Find Dana Cutrone in Canal Street Station. Talk to her to activate an objective. You have to get her keys back from her boyfriend. Once in the apartment you'll find the Lumberjack Outfit . the room along with collectibles #4, 40 and 90.
Manual error
There is a misspelling on page 11 of the instruction manual, under objective indicator. It reads "Check you journal for more information" with the word "your" misspelled.
Phone Numbers
Go to any phone and enter the 18 numbers, in no specific order, to unlock Keeper of Secrets accomplishment. These can be found throughout the game on posters, graffiti, and pretty much anything else. Out of the 25, you only have to enter 18 to unlock the accomplishment, after that the rest are useless.
In the Grinders Lane stage, go to the room with the television. Press X when you see "Switch Channel". Popeye The Sailor will start playing.
Potato Sack Outfit
In Chinatown, there is a flashing object near the Darkling portal. Shatter the glass and grab the Potato Sack Outfit. Sitting against alley wall near metro exit.
Roadworker Outfit
At City Hall Station enter the train to grab the Roadworker Outfit.
Secret Phone Numbers
Sure, you've called every number you've found on those hard-to-get Collectibles, but you certainly haven't found all of the phone numbers. Chances are, you've overlooked a phone number or two without even knowing it as you ripped out a goon's heart. All 25 'secret' phone numbers are scattered throughout New York and can be seen on anywhere from flyers and storefronts to garbage cans and posters. Dial 18 of the 25 on a phone ( in no specific order ) to unlock the final secret of the game.