Bingo.

The look on Sinclair's face right now is one of pure satisfaction. This is it. This is their sub bay, this is their way out. This is officially the end of the road for his life in Rapture, and thank every god in every religion for that. Thank everything and everyone that could possibly ever be thanked for that.

This is their door.

...Now how do they get in.

Sinclair laughs and gives Jack a solid clap on the back. He's the one who found it, after all, and Sinclair didn't expect that listening for the thickness of the wall would occur to Jack. That was pretty clever, for him.

But it's a brief celebratory moment before Sinclair gets to searching the wall for a seam, a button, anything at all that sticks out. But there's nothing on the wall except...

A Sander Cohen poster. Sinclair will never understand what Ryan saw in that guy.

He approaches the frame and cautiously pushes it to one side.

...The wall is bare behind it.

He pushes it to the other side,

and there it is. A small panel cut into the wall. He pushes on the edge of it and it swings open

revealing a keypad.

There's a code.

"Oh hell," Sinclair sighs. "Alright, let's find this damn thing. He's got it in his office somewhere."