Summary: Each year in the Australian outback, the dry season leaves five top predators- giant stingrays, sawfish, bull sharks, and freshwater and saltwater crocodiles- stranded in waterholes with limited food supplies. Zeb sets out to find out how each of the giants has adapted to the environment and which one is the ultimate king of the pool. With the help of local experts, Zeb gets up close with a bull shark’s sharp teeth, wades through knee-deep water in the dark of night searching for a stingray.

Summary: The giant eel is a massive, flesh-eating, wall-climbing, air-absorbing, snakelike fish that can attack like a crocodile and live upwards of 100 years. So, of course, Zeb goes in search of two of the largest species. First, in New Zealand, Zeb hunts for the New Zealand longfin eel and goes fishing with the locals, who use a traditional technique to lure the legendary monster. Then, in the Solomon Islands, he'll look for the elusive giant mottled eel.

Summary: The Murray cod can grow up to 6 feet long and weigh more than 250 pounds, and is rumored to eat everything from birds to snakes to possums even its own kind. But humans have been encroaching on the cod's river system, and now these enormous fish are rarely seen in the wild. Zeb travels to Australia in the hopes of experiencing this behemoth's size and power for himself.

Summary: Kamchatka, Russia, is one of the wildest and most remote locations on earth and is home to the largest salmon population on the planet but why? Zeb travels to the Far East to explore this salmon paradise. Determined to catch as many salmon species as he can, Zeb joins a team of kayakers and locals to explore some of the area's more than 14,000 rivers.

Summary: A mammoth catfish that has allegedly stalked, attacked and killed people can be found in the Indian Himalayas. Dr. Zeb Hogan investigates reports of the goonch. With the help of a local guide, Zeb sets out to examine the scenes and speak with eyewitnesses who recount the attacks - One recalls a young man who was fatally pulled under water while bathing; another describes a goonch dragging a 1,000-pound buffalo into the river.

Summary: One of the oldest and most bizarre-looking freshwater fish on the planet can be found in the American Midwest. That's where Dr. Zeb Hogan travels to find the paddlefish. It once teemed throughout the Mississippi and Missouri River systems, but its population has plummeted disappearing from four states and rapidly decreasing in others. Zeb teams up with biologists and conservation officers to better understand what's causing the decline of this American behemoth.

Summary: Dr. Zeb Hogan travels to one of the world's largest waterfalls in Laos, where each year millions of fish climb the falls to spawn. But little is known about their exact migratory route, and plans to dam the channel could place the lives of the fish, and the millions of people who depend on them for their livelihoods, at risk. Zeb and a team of world-class kayakers navigate the waterways with specially equipped kayaks, designed to take measurements of the rivers below them.