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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?

marked as duplicate by agent86 May 10 '13 at 1:20

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

  2. Find the switch behind the counter and use it.

    enter image description here

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

    enter image description here

    Go through that door and go downstairs, where you will find a Power to the People machine. Use this machine.

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

    enter image description here

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