Every day, every moment, an epic battle is raging across the globe. It's happening in the ocean. And the evidence is both highly visible and totally hidden, depending on your perspective. In this short, the tale of an arms race involving trillions of sea creatures--and why their struggle is vital to our survival.

Reporter Ari Daniel visits with Willie Wilson, who studies phytoplankton--aka microscopic plant-like creatures--at Bigelow Laboratory in Maine. There's a war in Willie's test tubes. A certain sort of phytoplankton known as coccolithophores are engaged in a surprisingly complicated arms race with deadly viruses. A virus is problematic enough when you're a human. Now imagine being a single-cell plant and mixing it up with the hugest virus you've ever seen. The coccos (as we've taken to calling them) are outgunned, but they won't go down with out a serious fight.

Ari and Willie explain how our itsy-bitsy heroes take arms against (literally) a sea of troubles--and how this battle, and others like it, make life on Earth possible.