The Universe is expanding but why is it accelerating? For thousands of years we've believed that the entire universe unfolded from its light. However the real truth about the cosmos lies not in what meets the eye but in the darkness. A mysterious new reality is emerging. A strange dark matter somehow binds stars and galaxies. And an even more enigmatic dark energy is causing the expansion of the universe to speed up. Combined dark matter and dark energy make up 95% of the universe. But their actual nature remains a mystery. This discovery challenges our understanding of the fundamental laws of nature. As far as we know now the only way to really attack this problem is by mapping the universe through galaxy surveys. People always have created maps as essential tools to help them define explain and navigate their way around the world. People always have created maps as essential tools to help them define explain and navigate their way around the world. That's the analogue purpose of the next generation maps of the universe like DES or PAU: solving the riddle of the accelerating universe. This is the story of a brilliant group of scientist whose are the next big step in untangling the enigma. The tale of how the most powerful camera ever built was fitted to a giant telescope to carry out the next greater map of the universe. This highly ambicious endevour to discover why is the universe speeding up brings in the era of giant cosmic maps.