Significant marine pollution and algal bloom outbreaks are creating eerie dead zones in North America's most biodiverse estuary. Dr. Tiara Moore, along with Dr. Craig O'Connell, explores whether Bull Sharks can persist in the Indian River Lagoon, a vital nursery, despite the oxygen-depleted waters. Her mission could unlock the secrets to shark survival in changing oceans.

In Indonesia's Raja Ampat Islands, a team of researchers hunt for one of the region's last living leopard sharks. But as they venture deeper into the unknown, the journey brings them face to face with some of the weirdest and wildest sharks on earth.