Gruber's team of researchers work day and night. In this episode they record a shark's vital statistics while it's in a state of tonic immobility. Before releasing it, they take a DNA sample. Enjoy!

At times, Doc Gruber's research requires the team to dive right into shark-infested waters! Their line of work certainly isn't for the faint of heart! Enjoy.

Nathalie and Jim get up close and personal with tiger and lemon sharks, trying to get the best footage while taking care not to disturb or excite the dangerous animals.

The team's divers conclude their filming and come back to the surface unharmed. We learn more about current developments in the prevention of shark attacks.

In this episode, Doc Gruber and a colleague are testing a shark repellent. If effective, it could help save the lives of divers, swimmers and surfers all over the world.

Here's some more stunning underwater footage. This time it's hammerhead sharks and stingrays, a wahoo and some striped eels, all filmed near the Cocos Island in the Caribbean. Take a look!

Samuel Gruber's team films white-tipped sharks and barracuda feeding at night off Cocos Island. Enjoy!