The plaque on the wall says:
Let us all play hide and seek,
Though the room has sprung a leak.
But who shall seek and who shall hide?
That is where the riddle lies.
And with the water rising thick,
I recommend you make it quick.
The one who seeks is seldom seen,
And of this fact he's very keen.
He keeps it secret, close and quiet,
But to free you all, he cannot hide it.
One more thing before you play,
Underwater is where you must stay.
The room is a giant fish bowl - this is obvious (after examination), given the rounded edges of the glass, the distorted view beyond, the little plastic castle and the pirate chest, all on pink gravel. At the offset, however, there is no water in the fish bowl. The room beyond is visible, but it is completely empty and seems to be comprised only of walls with no doors.
As the plaque is read, water begins to fill the bowl and the room beyond, and the under-gravel filter kicks in, making standing hard.. Everything goes dark when the last word is read and it remains completely dark until the seeker is determined, at which point the bowl is full and the water overflows to the room beyond. Jumping out of the fishbowl is not an option, as the fall would kill the jumper. Once the seeker is chosen, the fish bowl illuminates, but the only light is the small fish-bowl light, and the participants will find they share space with hungry fish, much larger than they are.( Directions. )