The hidden entrance

Your sub floats right up to the entrance and you tether it down so it remains relatively in place. The entrance is a little too small for the sub so you put on your pressure dive suit to leave the sub.

You walk out into the ocean. You can feel the cold ocean water against the suit. The weightlessness and free movement is a nice change from sitting inside the Yellow Rocket.

You quickly inspect the tethers holding the sub in place and make your way to the hidden entrance. If you hadn't been taking note of every last detail, you would have easily missed it. The only thing that draws your eye to it now is the sub floating just a few feet away. You open the door and see a path leading down under the city.

You make your way inside and there's no light source for your eyes as you close the door closed behind you. You turn on the lights on the front of your dive suit and you can see that you're in a short hallway that leads into a small metallic room. You walk into it expecting nothing to happen but a metal door slams shut right behind you with a loud bang.

The room goes red and you turn around quickly. Your heart starts pounding through your chest as you desperately try to find a way to open the door. The sound of machinery whirring fills the room. Whatever made this room can't be too happy with your unexpected entrance.

The room starts to drain of water and breathable air fills the room.

Once the water is completely drained and you're left dripping in the middle of the room, the door opposite where you came from starts to open.