In France, Germany, England and the United States, scientists and whistleblowers have embarked on a vertiginous hunt to find the oil and gas wells abandoned by the oil industry. What they reveal is staggering: between 20 and 30 million wells are left behind on all continents. An infinity of leaks that constitute the ghostly legacy of the global oil exploitation history. For most of them, these old drillings have not been plugged and are leaking into the seabed, underground or into the atmosphere – dangerous materials for the environment and for our health: oil, but also methane gas with a very strong greenhouse effect or underground substances loaded with toxic substances.