CNN Anchor Boris Sanchez returns with a descent into the heightening conflict between an ancient predator and their modern-day competition for prey.

Humans kill 100 million sharks worldwide each year, threatening one-third of shark species with extinction. Despite warnings that sharks are endangered globally, some fishermen say the shark population in the US is out of control, and the rate at which sharks are feasting on their catch is crippling the fishing industry. However, some scientists disagree, arguing that depredation may be due to overfishing and depleting prey sources. Sanchez speaks with parties on both sides of the issue, bringing their concerns to government regulators and even free dives with the sharks himself.