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The Sinking City: Lost at Sea Main Case Walkthrough

As soon as you exit Grimhaven in the Sinking City, there will be a cutscene and you wake up in your hotel room, starting the “Lost at Sea” Main Case.


Go to the Expeditions Headquarters at northern Coverside, crossroad Asher Rd/Hubert Ave.

 Expedition-Headquarters-Map---Coverside----Sinking-City-2019 camzillasmom.com

Collect all the Evidence at the Expedition Headquarters. Then, head over to The Oakmont Chronicle (Newspaper Symbol on the map).

Go to the Archives Desk.

 Archive-Search-Expedition---Newspaper--Coverside----Sinking-City-2019 camzillasmom.com

In the Archives Research Window, select “Burned newspaper” at the left.

Select 3 criteria:
Period: After the Flood
Section: Advertisements
District: Grimhaven Bay

 Research-Lost-at-Sea---Newspaper-Archives----Sinking-City-2019 camzillasmom.com

Evidence found:
Ship Freight Advertisement

You’ll find a person’s name and address:
Captain Jeremiah Sanders
Pier 3, Oakmont Port, Grimhaven Bay

This is the next stop:

 Ship-freight-location camzillasmom.com

When you arrive at the pier, you hear a man yelling and ask for help. Kill the sea creatures and talk to him again.

Evidence found:
Sanders has fled (Mind Palace)

Then go to Pier N3 to collect the evidence. After you picked up all the evidence there, you know that you have to head to the Hospital:

 Hospital-Map---Coverside----Sinking-City-2019 camzillasmom.com

At the Hospital, talk to the front desk doctor. If you want to, you can pick up the “Field Research” Side Case from him.

Get all the Evidence from the Hospital.

At the Hospital, talk to the front desk doctor. If you want to, you can pick up the “Field Research” Side Case from him.

Then, go over to the Diving Suit Factory:

 Diving-Suit-Factory---map-2---lost-at-sea----Sinking-City-2019 camzillasmom.com

Go over to the Diving Suit Factory and pick up the Diving Suit. Now take the boat and go to the “Devil’s Teeth” at the south of the map. To go there, get on the boat that is parked next to the ship you investigated earlier.

You arrive at Devil’s Teeth. Go over to the handle and use it to dive.

 Dive-Start---Devil-s-Teeth---lost-at-sea----Sinking-City-2019 camzillasmom.com

Follow  the glowing Chemical Lamps into the glowing light. Don’t hesitate to jump down at some point. Just look around to see the lamps. You’ll enter a cave. In the cave, take a look at the crazy scientist.

Evidence found:
Madness emanates from the Scientists (Mind Palace)

Follow the lights inside until you get to the body with the camera picture. Take a picture of the body.

 Body-Underwater-Cave---Devil-s-Teeth---lost-at-sea----Sinking-City-2019 camzillasmom.com

Evidence found:
Innsmouther Attacker

Go over to the red haired guy next to the fish statue and talk to him.

Evidence found:
Mad Scientist (Mind Palace)

At the Mind Palace, connect:
Mad scientists <-> Madness emanates from the scientists

Enter “Mind’s Eye” and look at the Fish Statue next to the red haired man.

 Fish-Statue---Devil-s-Teeth---lost-at-sea----Sinking-City-2019 camzillasmom.com

Hold X (PS4) to see the vision. The Rift will open and you can enter it.

 Rift---Devil-s-Teeth---lost-at-sea----Sinking-City-2019 camzillasmom.com

There are 3 glowing blobs in the area. Go to them to reveal their story. Then number them in the following order:

 Rift-Numbering-123---Devil-s-Teeth---lost-at-sea----Sinking-City-2019 camzillasmom.com

Evidence found:
The Innsmouthers’ Attack
The Underwater Artifact (Mind Palace)

At the Mind Palace, connect:
The Underwater Artifact <-> Burned Documents
Alberts Saviours <-> Mad Scientists

Now you have “Madness on the Titania”  and “The Titania Incident”.

Combine to:
Albert was the source of this madness.

Combine all to:
Save the survivors

Return to the surface and over to your boat. You’ll wake up in the hotel room.

Head to the Manor at Oldgrove – it’s a manor symbol on the map – and talk to Robert Throgmorton.

Case Closed

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About The Sinking City

Release: June 28, 2019
Developer: Frogwares
Publisher: Bigben Interactive
Official Website: https://frogwares.com/