Nanu and Otto are off on a climbing adventure - to the top of Lion Mountain! Otto is a born explorer, just like his grandma, who is brave and bold and can't resist the urge for adventure. But Nanu is having a forgetting day. She forgets her backpack and the name of the mountain ... and then she forgets the way home and leads them deep into the forest. Can Otto remember all the things Nanu taught him about being a great elephant explorer and guide the expedition home?
