A crystalline monolith appeared in Earth in the time of the first man-apes. It turns them into thinking creatures from which we humans originated.
after Thousands and thousands years, the monolith of the same kind is found in the Moon. Scientists are dazzled about the thing. Many theories aroused. The monolith when found started to emit some unknown radiation which was detected leading to one of the Saturn’s satellites.
A mission started to Saturn to find anything about the monolith and its purpose. During the flight, there happened many failures among which the astronauts having killed by the AI computer HAL is worth to mention. But nevertheless, one member of the crew succeeded to reach the Saturn’s satellite. The monolith there emerged to be the Space Gate to the world of its creators. In the end the man literary became one of the aliens consisting of no flesh and blood but pure radiation moving with the velocity of light.