Often described as the oldest of the sciences, astronomy is today one of the most modern and dynamic. In four corners of the planet, giant telescopes are affected as our eyes pop out of the ground and affect our understanding of the Universe. In the most important observatories in the world, in Chile, Hawaii and the Canary Islands, a new generation of astronomers, engineers and technicians are writing the next chapter of our knowledge of the Universe. This documentary takes us to meet these "star people" to discover what makes their hearts beat, but also to understand how astronomy decrypts our past and shapes our future.