In 'Four Fish,' Paul Greenberg embarks on an investigative journey into the complex world of fish, the last wild food on our tables. Focusing on the mainstays of the seafood menu—salmon, sea bass, cod, and tuna—Greenberg uncovers the stark reality behind our consumption patterns and the impact on oceanic ecosystems. As he delves into the histories and current states of these species, he introduces readers to the intricate balance of wild and farmed fish in the marketplace. From Norwegian mega farms to Fair Trade certified fishing in native waters, and through the murky waters of contaminants like PCBs, Greenberg advocates for the oceans' future. His exploration paves the way for a dialogue about sustainable and ethical seafood, challenging us to consider how we might reverse the damage inflicted on the seas and ensure the continuance of its bounty.