How do you access the locked area in Poseidon Plaza? [duplicate]

I've been playing through Bioshock again, and there's an area in Poseidon Plaza which I can't figure out how to get to.

This is the place on the map: Poseidon Plaza map
click to enlarge

This seems to be the (locked) entrance to it: enter image description here
click to enlarge

How do I get in there?

bioshock

Pictures about "How do you access the locked area in Poseidon Plaza? [duplicate]"

How do you access the locked area in Poseidon Plaza? [duplicate] - Semi Open White Wooden Door

How do you access the locked area in Poseidon Plaza? [duplicate] - Key with trinket in shabby door

How do you access the locked area in Poseidon Plaza? [duplicate] - Black and Grey Keys

Quick Answer about "How do you access the locked area in Poseidon Plaza? [duplicate]"

Go into Sinclair Spirits (left to the view on the second screenshot).

Find the switch behind the counter and use it.

A door on the wall opposite to the counter will open. ...

After returning upstairs, the previously locked stairwell will be unlocked.

How do I get downstairs Sinclair Spirits?

The mechanism that removes the grate is inside Sinclair Spirits (the shop with the papier-m\xe2ch\xe9 splicers lining the entryway). Go behind the counter to press the button, and the storeroom off of the room you're in will be unlocked. Head down there and take everything from the safe.

How do I get into Poseidon Plaza?

Poseidon Plaza is only accessible to the player after Jack has photographed Kyle Fitzpatrick's corpse and placed the picture in Sander Cohen's masterpiece. After passing through the Frozen Tunnel Jack emerges in the dark and dusty Plaza.

Bioshock Secret Downstairs Fort Frolic

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Images: Pixabay, Jonathan Petersson, Andrea Piacquadio, George Becker