Quid Pro Quo is a main quest in The Sinking City that follows right after “Lost at Sea”.
1 – Oakmont Police Department
Go to the Archives of the Oakmont Police Department.
Use the case:
The Fate of the Expedition
Select those criteria:
Crimes: Violent Crimes
Subjects: Suspects
Evidence: Instruments of Crime
Evidence found:
Police Report No 19-0451
In the report, there is an address. Go to this location at the Fish Market.
2 – Fish Market
Enter the market and the conversation will start. Talk to Anna. She’s the one in front of the “eye” poster.
Evidence collected:
Anna’s Request
Oakmont is starving (Mind Palace)
EOD is giving away fish (Mind Palace)
In the Mind Palace, combine:
Oakmont is starving <-> EOD is giving away fish
3 – EOD Fish Storage
Go to the location and talk to the guy in front of the storage building.
Evidence collected:
The Guard’s Testimony
A Key to the Fish Storage
Go down to the basement and use “Mind’s Eye”. Look at the dead fish and animal and activate the vision.
Evidence collected:
The fish is poisonous
You will get a ghostly vision to follow. Follow it to a fish pile on the floor at ground level.
Look at the fish pile and investigate the bottle.
Evidence collected:
Lab Flask
In Mind Palace, combine:
The fish is poisonous <-> EOD is giving away fish
The vision rift will open at ground level and you can put the events in order:
First the event at the fish box:
Then the event at the fish pile on the floor.
Then the upstairs event.
Last one is at the stairs.
Evidence collected:
The events in the Fish Storage
A mention of a professor (Mind Palace)
In the Mind Palace, combine:
A mention of a professor <-> Lab flask
Evidence collected:
The Poisoner and the University
Now go down the basement again and activate “Mind’s Eye”. There is a hidden passage close to the locker.
Look at the tools on the table.
Evidence collected:
A secret chamber in the warehouse
Talk to the guard outside and ask where the University is.
Evidence collected:
The Guard’s plea
The Guard is afraid of Anna (Mind Palace)
Return to Anna at the Fish Market and talk to her. Next stop University.
4 – University – Department of Medicine
When you arrive, the door has a big “closed” sign on it. Talk to the guy next to the door. He sends you to the “Department of Medicine”, which is at the south of the biggest University building. Talk to the receptionist.
Evidence collected:
The Student’s Request
A key to the lab
Stay on ground floor. Behind the receptionist there is a “EOD is banned” poster on the wall. Look at it.
Evidence collected:
EOD is banned!
The EOD ranks are swelling (Mind Palace)
Go down to the basement and clear it. Talk to the receptionist again.
Evidence collected:
Westerbrook has access to poison.
You received the key. Go up the second floor now. Melee the door with the locker on it and go inside. Inspect the medicine cabinet and activate “Mind’s Eye”. Follow the ghost to Dr. Cavendish’s office and inspect the soap bar at his desk with Mind’s Eye again.
Evidence collected:
George Cavendish made a spare key (Mind Palace)
Go to Mind Palace, combine:
George Cavendish made a spare key <-> Westerbrook has access to poison
Evidence collected:
The Poison Thief
5 – City Hall
Go to the City Hall and use the archives.
Choose Evidence:
The Poison Thief
Select criteria:
Subjects: Citizens
Registry: Citizen Records
District: Advent
Evidence collected:
George Cavendish Profile
6 – Apartment of G. Cavendish
Go to the second floor and melee attack the lock on the door to get inside. Go to the bedroom/office. There is a piece of paper on the desk.
Evidence collected:
The Professor’s Fact List
Look at the pin board next to the desk and collect all you can.
Evidence collected:
EOD’s suspected crimes
Go to the Mind Palace, combine:
EOD’s suspected crimes <-> Secret chamber
There is a door with a lock on it. Melee attack to open and get inside. Activate Mind’s Eye, pick up the empty picture frame and reveal the vision.
Enter the vision rift and put together the events:
First the one at the table with the ring.
Then the one in the kitchen.
Last the one by the door.
After the conversation…
Evidence collected:
The poisoning was sabotage
Anna’s pregnancy was ordained
Go to Mind Palace, combine:
The poisoning was a sabotage <-> EOD ranks are swelling
Now combine:
Gearge sabotaged the EOD <-> The poisoned fish is spreading
Select your path
I selected: A desperate saviour
Return and combine:
Anna is pregnant <-> The guard is afraid of Anna
Now combine:
The EOD helps prevent famine <-> A zealous servant of EOD
Select your path
I selected: A filthy liar
Now I combine:
The EOD’s operations are shady
A desperate savior
A filthy liar
Talk to George, choose your path. I chose: I’ll help.
Evidence collected:
I can report George
A Full Flask of Ricin
George Cavendish’s Request
You can now go to either poison the rest of the fish, or report to Anna. I did report to Anna, since poisoning innocents isn’t my thing.
7 – Fish Market
Talk to Anna.
Evidence Collected:
I reported George to Anna
High-Ranking Member of EOD
Go down the basement of the fish market. The entrance is next to the two guys who are looking at a map. Fight the men.
Evidence collected:
Note to Maurice
Exit the basement. After the conversation: Go back to Mr. Throgmorton.
Case Closed
More The Sinking City Guides
The Sinking City: Fishermen’s House – All Evidence
Collect all Evidence at the Fishermen's House in The Sinking City.
The Sinking City: Hospital of St. Mary – All Evidence
Collect all Evidence at the Hospital of St. Mary in The Sinking City.
The Sinking City: Letters from Oakmont Walkthrough
Where to find the Letters from Oakmont in The Sinking City.
The Sinking City: Lost at Sea Main Case Walkthrough
Full walkthrough of the Main Case "Lost at Sea" in The Sinking City.
The Sinking City: Nosedive Main Case Walkthrough
Full walkthrough of the Main Case "Nosedive" in The Sinking City.
The Sinking City: Pier N3 – All Evidence
Collect all Evidence at Pier N3 in The Sinking City.
About The Sinking City
Release: June 28, 2019
Developer: Frogwares
Publisher: Bigben Interactive
Official Website: https://frogwares.com/






















