Instinct tells us that our world is three-dimensional. Based on this idea, scientific hypotheses have been built for centuries. According to the eminent physicist Michio Kaku, this is the same prejudice as the belief of the ancient Egyptians that the Earth was flat. The book is devoted to the theory of hyperspace. The idea of the multidimensionality of space caused skepticism and was ridiculed, but is now accepted by many reputable scientists. The significance of this theory is that it is able to combine all known physical phenomena into a simple construct and lead scientists to the so-called theory of everything. However, there is almost no serious and accessible literature for non-specialists. This gap is filled by Michio Kaku, explaining from a scientific point of view the origin of the Earth, the existence of parallel universes, time travel, and many other seemingly fantastic phenomena.