Steve and the team head to the remote island of Isla del Plata, off the coast of Mexico, which has the largest congregation of giant manta rays in the world.\n\nWorking with one of the world’s top manta scientists, Steve heads off to try and dive with these majestic giants. At the first glimpse of one from the drone, the team can’t believe their eyes – it’s as big as their boat! And once in the water, Steve is totally dwarfed by their presence.\n\nSteve also comes across a green turtle with a fishing hook stuck in its mouth. He tries as hard as he can to free it but with no success. Injuries such as this are common in these waters, so Steve heads to the local turtle sanctuary to see what is being done to help these turtles. While there, he has the amazing opportunity to release one of these turtles back into the wild.\n\nNext, Steve goes in search for an old Deadly favourite: the humpback whale. He has seen them in the wild before, but at this time of year, there is a unique opportunity to see one of the biggest babies in the world as both mother humpbacks and their calves are here. With the water like pea soup, Steve is unable to see them underwater, but he has another idea - to use the drone to get a bird's-eye view. Steve has never seen them this way before, and it is a great way to view them without disturbing them. The team also get to see the biggest limb in the world slamming down into the water – a deadly defence to add to their huge size and huge appetite!\n\nFinally, Steve has the unique opportunity to dive around Isla del Plata at night. This has never been done before, so nerves are high as the water could be full of predators. Steve makes friends with a curious pufferfish and watches a moray eel on its nightly hunt. However, the most surprising and incredible encounter of all comes as the turtle that Steve previously wasn’t able to help suddenly appears in front of him, lies down and allows him to remove the hook from its mouth. It provides an emotional moment that Steve will never forget.