News of a harrowing shark encounter at North Carolina's Frying Pan Tower sends underwater cinematographer Andy Casagrande and shark expert Kori Burkhardt on a dangerous quest to discover whether great white sharks are moving into the state's waters.

A 14-foot giant mako shark is spotted in the waters of Portugal's Azores region. Underwater cinematographer Joe Romeiro and his marine biologist wife, Lauren, search the teeming depths around the ancient islands to capture the beast on film.

The remote islands off the Eyre Peninsula in South Australia are believed to harbor some of the biggest white sharks on the planet. While local fishing reports suggest these giant sharks are still around, they are rarely seen.