Lake Baikal not only is the world's oldest lakes, it is also the deepest. It's 1,600 meters deep. It's also the clearest, with visibility to a depth of 40 meters. The lake is home to many endemic species that have undergone unique evolutionary processes. Observing unfamiliar creatures living in remarkably crystal clear waters is a sight to see. The cameras rolled for three months between the end of winter and summer to capture the hidden mysteries of the lake, including the habits of these uncommon animals and the unique mechanism that produces Lake Baikal's clear water.