This is a critical time for our animal characters. What is special about this year? Predictions are that 2017 is going to be spectacular.Vast swathes of Alaska are frozen for much of the year; in summer, the huge glaciers start to melt. This melting triggers the natural spectacle of the Alaskan Summer Feast.Steve Backshall will attempt a dangerous live TV first, landing on a glacier by helicopter and abseiling into and underneath the ice. He'll be looking for evidence of what ignites the summer feast and for answers about what makes the Gulf of Alaska so special.The sheer power of glaciers turns mountains into dust. This kick-starts a food chain in the seas which brings in the biggest animals of all coming to this feast - humpbacks and orcas. Matt Baker will be looking for these with a live helicopter off the coast of Tongass National Forest.Liz will be continuing her live brown bear adventure and we travel offshore to meet Alaska's version of Jaws - the salmon shark. We will also be meeting the people of Alaska, getting an idea of what it's like to live in this wilderness alongside so much wildlife.