TV Nanana, a dirt-poor television network, is bought out by the major streaming service Nanazon Prime Video... and the bigwigs of Nanazon waste no time laying off staff on a massive scale! The first ones they target are the Expedition Team, whose members succeeded in filming the legendary beast Kiina, because they haven't produced any hit programs since the Kiina story. So to avoid being laid off, the director Nanaoka, cameraman Nanamori, and assistant director Nanayama kick off an ambitious new program idea that major networks had sunk small fortunes into before and failed: to discover the buried treasure of the Banagawa House and broadcast it on TV.
As the three of them begin their low-budget excavation project, they discover a doorway to the depths of the earth, but many obstacles await them in the cave that lies beyond. Pitfalls, food shortages, huge swarms of bats... and beyond all that, they stumble into a castle town where a general of the Banagawa House and his retainers attack them to protect the buried treasure. A mysterious ninja even shows up on the scene. Will the trio ever unearth the buried treasure? And what's to become of TV Nanana?!