Sinister: space

I was swimming in the mediterranean sea and something of strange attracted me ; i swam until the bottom of sea (10 metres) and i saw a door . I came to the surface, for air, and then to the bottom of the sea, and with my enurmous surprise i saw the door opened in a dark hole ; there's no hause , there's no building , only the right door. Air again in the surface and i crossed the door................................no water , no sea-weeds , only green jelly with fish of gum , and a lot of doors (endless). Only a dream. Before sleep i listened TBWTAS. Marco#7.