In this The Sinking City Quid Pro Quo Walkthrough, we will guide you on how you can complete the main case Quid Pro Quo in The Sinking City. Quid Pro Quo is the third case in the main campaign of The Sinking City and in this case, you will need to find what happened to Professor Harriet Dough after she was kidnapped from the site under water. During this case, you will also get to know more about the secret organization operating in Oakmont.
You will get this case right after you solve the previous case Lost at Sea and Robert Throgmorton will ask you to find out who took Professor Harriet Dough. Our The Sinking City Quid Pro Quo Walkthrough will help you find all clues in each location of this main case and also how you can opt for the best options to help solve the case in the most efficient way as possible. Without further ado, let’s start with the walkthrough.
Quid Pro Quo Walkthrough – The Sinking City
Our The Sinking City Quid Pro Quo Walkthrough will help you solve the Quid Pro Quo main case in The Sinking City.
Starting Up
To begin with, you will have a note from your previous investigation which will help you to begin your investigation in Quid Pro Quo. Pin the evidence The Fate of the Expedition and head towards the Police Station because you have to search their archives for some specific crimes. Once you are at the police archive, with the evidence pinned, choose Violent Crimes in Crimes tab, Instruments of Crime in Evidence section and Suspects in the Subjects section.
These are the three parameters that you will need to search in the archives. Once done, this will give you a new lead Police Report No 19-0451 which will point towards the Fish Market. Make your way to the Fish Market in The Shells where you will come across a woman next to a board with a symbol. She is Anna and you have to interact with her. Interacting with her will give you the basic details about the secret EOD organization and also some problems that EOD had recently in their fish storage. Pin the evidence of Anna’s Request.
Before moving on, you will have some new clues in your Mind Palace so open it up and combine the clues Oakmont is Starving with EOD is giving away fish. Combing these two clues together will deduce that The EOD helps prevent famine and it will be added to your Mind Palace for future reference. Now that you are done with this part, you can start working towards your next task which is to inspect the EOD’s Fish Storage and find the man responsible for the theft.
Inspecting the Fish Storage and Tracing the Culprit
Naturally, your next stop is the Fish Storage which is located in the west of The Shells. You can use the Fast Travel to go there instantly however if you have not unlocked the Fast Travel point yet, you can simply head to Hawking Lane which is between Warren Road and Liberty Road. The storage is located at the end of Hawking Lane where an infested area begins. Outside the entrance, you will find Daryl Grimes who looks after the storage. Speak to him.
When you get the prompt, tell him the password ‘I Serve the sea’ and continue the chat normally. Complete the questioning and then move inside the storage to check it for clues. Beware because you will encounter some Wylebeasts inside so make sure that you have some ammo on you before you go in. Kill the Wylebeasts and you will be free to explore the area at your own will. Coming to the clues, right after entering the warehouse, check the harpoon stuck in the box.
After that move on and check the crafting materials, a box with fish in it, and some cabinets with loot in them. Once done, go down the stairs and check the dead creature next to a fish. Inspect it with Mind’s Eye and you will get to know that the creature died after eating the fish. This will allow you to get some more clues. Your next step is your Mind Palace. Open it up. Combine The fish is poisonous and EOD is giving away fish.
This will deduce that The poisoned fish is spreading. Now close the Mind Palace and use Mind’s Eye and a small creature will appear guiding you back upstairs. Follow this creature and it will lead to upstairs next to a fallen down box of fish with a bottle next to it. Examine the bottle and it will give you another clue. Before heading to the first floor, go back down the stairs again and reach the wall at the end where you will get another prompt to use Mind’s Eye.
Use it to open the secret torture chamber inside the warehouse. Once it is open, inspect the room and make your way to the first floor of the storage. Once up, you can check the shop model on the table, collect some bullets and loot from lockers. You can also inspect the tools lying next to the ship model. Now you will get the prompt to use Retrocognition and figure out what happened at the storage. Go back downstairs and enter the portal.
It will show you four different spots. Check all spots once to see what they are and then you can choose them in the right direction. The correct order of the crime scene is:
Robber poisoning the fish>Robber tipping over the fish>Daryl running to get his harpoon>Daryl shooting the harpoon
Now you will have the key evidence as well as all the evidence for the EOD Fish Storage. You can go to Daryl and ask him about the torture room as well as let him know what exactly happened. A rare trophy opportunity is present in this chat. At the end, when Daryl asks you to keep the scene a secret, promise him that you will do so. Now go back to Anna and tell her the complete story. In the end, when Anna asks about Daryl, tell her Daryl missed the intrusion. His will unlock the trophy/achievement.
Now that you are done with this bit, you will have a few new clues and leads regarding the case. Before proceeding, open your Mind Palace and connect A Mention of a professor and Lab Flask to deduce that the Poisoner and the University are connected somehow. Now your next stop is the university. The university is located in Reed Heights so if you have unlocked a fast travel point there, use it to get there quickly otherwise you will need a boat to get there.
Exploring the University and Tracking Down the Professor
When you reach the university, you will find out the building is closed. However, a stuttering man is standing next to the gate. Speak with him and he will point you towards the Medicine Department of the university. Head there and speak with Samuel on the counter. He will agree to test out the residue in the flask if you help them clear the basement of all the Wylebeasts. There is plenty of ammo and supplies on this floor of the university to make sure that your search is thoroughly before going down to the basement.
Now head towards the basement and you will come across some Wylebeasts. Kill them all and explore the basement for some supplies and clues. Check the crate, autopsy table, pick up the two experimental logs and the strange device for conducting experiments. You can unlock an optional fight here. If you press the red big button for a few times, the big Wylebeast will be awakened however it is not easy to kill. This will also unlock the Reanimator trophy/achievement.
Once you are satisfied with the exploring, go back up and tell Samuel that the basement is clear and you want the test results now. He will take a little time and will return soon. Now go through the following questions and you will end up with the key to the first floor. Go up and check the clues which include a drawer, a note about Westerbrook’s office closure, notes from his table, a draft of an article from Cavendish’s office and the soap which has the key print.
Use Mind Eye and inspect the soap which will unlock a trace heading back to Professor Westerbrook’s office. Follow the trail, shoot the lock to open the door and inspect the poison bottles inside. This will help you identify that Professor Cavendish is the man who poisoned the fish at the EOD Fish Storage. Open your Mind Palace to connect the clues George Cavendish made a spare key and Westerbrook has access to the poison. This will help you identify him as the poison thief.
If you have looked at everything, your icon on the map should be green now. If not, have one last sweep, go down to Samuel, have your last discussion if you still have to ask him something and exit the university. Pin the evidence The poison thief. Now your next task is to find Professor Cavendish’s residence and there is only one place where you can find this information, the City Hall. It is located in the Advent district so get there asap. Once there, go to the back and access the City Hall Archive.
Here, you must choose Citizens in the Subjects tab, Citizen Records in the Registry tab and Advent in the District tab. This will give the file George Cavendish profile which shows his address. Open your casebook and pin it. Now you must head to his flat which is located on the Michael’s Rd between Carpenter St and Constitution St. After entering the building, go up the stairs and before entering the flat, check the baby stroller for a note and then shoot down the lock on the door.
Inside, you can start looking for clues now. Check the rink on the table, suitcase, the desk and two newspaper clippings from the board on the wall. To get inside the small locked room, shoot the lock again and check the dresses inside. Pick up the picture and use your Mind’s Eye to unlock a clue. Now go back and check the board on the wall. Now open your Mind Palace and connect EODs suspected crimes and Secret chamber in the warehouse. This will deduce that EOD’s operations are shady. Now you can enter the portal to figure out what happened with Retrocognition. Inspect all three sites and then connect them in the following sequence.
Table Talk>Kitchen fight>Anna leaving the apartment
As soon as this is done, you will trigger a cutscene and when you wake up, Professor George Cavendish will be in the apartment. Speak with him and in the end, you will be presented with two choices. One of them is helping Cavendish poison the fish while the other is telling Anna the truth and killing Cavendish. If you go with the second choice, Cavendish will attack you instantly and you will have to kill him. The two choices are detailed below.
Case Choice #1 – Helping Cavendish
To pick this path, open your Mind Palace and connect the clues The guard is afraid of Anna with Anna’s pregnancy was ordained. This will deduce A zealous servant of EOD. Now choose the question mark and select a Filthy Liar. Now go back to clues and combine The EOD ranks are swelling and The poisoning was sabotage to deduce that George sabotaged the EOD. For the final deduction, click on the question mark and you will unlock Help George to undermine EOD.
If you decide to help Cavendish, he will ask you to head back to the EOD Fish Storage and poison the fresh lot of the fish that has just arrived there. You might need to kill the new guards if you reported Daryl earlier because you will find him inside the torture chamber inside. Go in and poison the fish. Check the torture chamber to find the dead body of Daryl inside. Now go out and tell George that you’ve poisoned the fish. He will inform you about Fred and give you the password to tell him.
Case Choice #2 – Helping Anna
This is the second choice that you can have in this case which is to kill Cavendish and tell Anna that the murderer has been dealt with. To initiate this phase, after killing Cavendish open your Mind Palace where you will have some new clues to play with. Combine The poisoning was sabotage with Anna’s pregnancy was ordained to deduce that George sabotaged the EOD. From the question mark, choose a dangerous psychopath.
Now check the clues again and combine The guard is afraid of Anna with Anna’s pregnancy was ordained which will give you a zealous servant of EOD. Now you can make the conclusion at the question mark tile An Honest benefactor. At the final tile, choose Help Anna and the City which will the final direction for this case. Now you must head back to the Fish Market and tell Anna everything. She will tell you to meet Maurice in the basement. Go down and collect the loot from there.
You will be attacked by three men in the last room so you must have your weapons ready. Check their bodies and you will find a note which will tell you that EOD was playing along and they wanted to get rid of Reed and hence Anna set up a trap for that. However, their plan has been shattered and Reed still lives.
Finishing Up
To finish the case, you will meet up with Fred in the same basement. This is the same for both choices that you make previously. However, only the location where you meet Fred will change depending on your choice. If you helped George, you will meet him inside the basement and you will need to tell him the password George tell you. If you helped Anna, you will meet Fred while coming out of the basement after killing the EOD hitmen. Fred will agree to help Reed to find Professor Harriet Dew in return for a favor. Return to Robert Throgmorton at the Throgmorton Mansion to conclude the case and begin the next case Fathers and Sons.
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