Last of the Giants - Season 1 Episode 5

Two giant fish, one heart-pounding mission in the dangerous Amazon jungle that brings Cyril and the crew face-to-face with armed poachers, ravenous piranhas, hunting caimans, massive anacondas and a terrifying flash flood. Their mission: protecting not one, but two of the most massive freshwater giants on the planet: the armour-plated pirarucu, and the gargantuan Piraiba. These elusive giants are under threat from human activity, and the team must find them in order to collect non-intrusive DNA samples for scientists desperate to conserve them, but the jungle won't make it easy.