Dan O'Neill is on a mission to find, film, and measure the biggest living crocodiles. Dan joins Dennis, an indigenous saltwater crocodile guide in Australia's Northern Territory, hoping to track down a legendary giant male lurking somewhere along the Mary River.

Dan O'Neill is on a mission to find and film Earth's biggest wild lions. Bringing a prehistoric giant back to life with CGI, he'll learn about the biggest cat to ever exist, explore a lion's evolutionary secrets, and find out what we can do to protect the giant lions of today.