The world we live in is like an unopened book. Different time and space planes form the pages of the book. They are layered on top of each other and appear to be one world. But once the book is opened, you will find that our world is just one page of the book;
Some people say that the thirty-three levels of outer heaven, the Nine Springs of Netherworld, and the eighteen levels of hell all exist, but they are hidden and we cannot discover them for the time being.
Finally one day, an alien plane like the sand of the Ganges began to appear around us, and the Book of the World began to slowly open. The thirty-three levels of outer heaven, the Olympus Mountains, and the eighteen levels of hell, everything began to slowly emerge!
In our world, countless secret realms appear every moment, like parallel worlds, waiting for people to explore. These people who enter the secret realms to explore are called secret realm apostles!