There are around 72 total items including random Medals in Hydrophobia: Prophecy but your concern should be documents and objects. Since collecting all documents and objects scattered throughout the game will unlock your Private Eye achievement or trophy.
We have listed down every document and object that you can find in the game in order so you can keep track of all the collectibles and revisit certain chapter if you miss anything.
Hydrophobia Private Eye Achievement/Trophy Guide
Below are all the locations of the objects and documents that you can find in Hydrophobia.
Act 1 (Kate’s Apartment)
Location. You’ll get this at the start
Location. Look at the table, in front of the couch.
Location. Near the arm-chair which is next to the couch.
Certificate of Achievement
Location. It is at the red table (1st floor).
Location. It is also at the red table (1st floor).
Weighted Wrist Bands
Location. At the arm-chair (1st floor).
Location. You’ll get it right next to the couch.
Location. Same as the Hand Grips spot.
Roy the Donkey
Location. It’s on the shelf.
Location. It is next to Yate’s dead body.
Queen of the world Replica
Location. Look at the desk which is next to the exit door (left).
A vision of the future
Location. At the same spot, on the floor.
Location. Look at the desk which is next to the exit door. (Right)
Queen of the World Anniversary
Location. You will jump into the metal beam right after the explosion; you’ll have to go right for the story to continue.Before moving right look for a metal pipe right in the front of you, so you can take a jump from it and swing to the next metal floor to get this!
Distribution Centre Alpha
Queen of the world anniversary guide
Location. There is a ladder in the room, climb up to it and find it.
Upper Security Complex and Security Office
Malthus Opens the Debate
Location. Right after you’ll leave the elevator’s shaft, you’ll see a dead body. Look on its left.
Location. You’ll now see some climbable bars, climb and you’ll get to it.
Location. It is on the table.
Location. You’ll see this on the floor.
10th Anniversary Commemorative Coin
Location. It is on the desk of the room where you found the first frequency key.
Location. It is on a desk, in the room with Billingham.
Location. It’s at the end of the same room.
Morton, Sitrep, Coming Storm
Location. Once you’ll collect the Billingham’s character profile from the desk you will get all of these.
Death or Glory: Malthusians vscornucopians (D)
Location. After the elevator has fallen behind Kate, go to the Elevator Shaft and into the secret room. Look at the dead body and you will get the Explorer Medal and the Collector Medal if you have not missed any other collectibles.
Elevator Shaft (Act 2)
Location. Swim to the elevator shaft and you will notice a door. Prepare for a long swim through the door into the hallway to reach this document. Look for a room with an air pocket to the left of the corridor if you need air.
It is rewarded if you collect all the collectibles in one breath.
Cycloconverters Operational Overview
Location. Look at the desk of the same room
Location. It’s next to the blue lockers, on the high area. This is only unlocked once you have completed the Cycloconverters B, so you’ll have to come back.
Maintenance (Act 3)
Anxiety No More
Location. It is right on the floor where the gas ceiling is leaked and is between the two fires.
Location. You’ll see a dead body when you’ll exit the vent, this is on it.
VFD Power Control
VFD Facility Overview
Location. It’s on the floor, same room where you hack the control systems.
Loading Bay Servers
The Prophecy of Malthus
Location. Look underwater in the yellow rails corner.
Launching Mankind’s Great Hope
Location. Swim into the flooded corridor right after you have distinguished the fire by opening the door, search at the yellow container.
You will now be awarded the “Collector 2” medal ONLY if you have collected all of the items.
Power Cell Access
From the Flames
Location. Once you’re done with the electrified wires, you’ll enter into a doorway, turn left from there and then take another right into another corridor. At the right side there are some breakable windows – The item is behind those on a machine.
Location. Follow the last route and instead of going left (into the 2nd corridor), go straight and you’ll see another breakable window. Look at the blue machine of that room.
Queen of the World Anniversary Flag
Location. You’ll kill some Malthusians after you’ll get out of the elevator; there is a bench on your right. Look at it.
Official Anniversary Big Boy Band
Location. On the bench of the third walkway (corner).
Official Anniversary Big Boy Hat
Location. Go straight from the Third Walkway and look for an Eat Stop, and search behind it.
Location. Look at the bench of the 4th walkway.
If you find anything missing, you can comment and I will add it up.