Earthquakes kill thousands of people across the world each year and are highly unpredictable. Now scientists are searching for the ultimate clue: a sign that an earthquake is coming, which could save many lives. Advancements in technology - and now artificial intelligence - could bring us closer than ever before to uncovering this holy grail of seismology.

We join trailblazing scientists in some of the world's most earthquake-prone countries, as they use groundbreaking technology to search for signs of imminent disasters.

From a husband-and-wife team in India who are tracking down natural gas that they believe could provide a clue. To Japanese scientists drilling thousands of kilometres beneath the seafloor to understand more about the Nankai Trough, a dangerous earthquake fault line. To Chinese scientists monitoring abnormal changes in the Earth's gravity.

These earthquake detectives will stop at nothing to decode these dangerous natural disasters.