The film depicts the history of native peoples who settled on the shores of the ancient volcanic lake (in a caldera at about 7000 feet), and on the islands. In the 19th century, some pioneers settled in the area, built a small town and even a small narrow gauge railroad, and some people lived on the islands. The film then explains how the tufa (salt towers) formed.
The lake, with no natural drainage, is three times as saline as the ocean. Brine shrimp and unusual insects live underneath the water.
Recent scientific discoveries have shown that bacteria life in the water uses arsenic instead of phosphorus for many critical proteins, and has given rise to speculation about how extraterrestrial life could evolve.
The lake (as is much of the surrounding area down to Mammoth Lakes) is in an ancient volcano caldera, that could explode someday as a supervolcano, and poses a risk to civilization not unlike that of Yellowstone.
Trailer from Nature Wonders, Travel Video Store: