Here's some info on the story.
The story sounds cool but, it's hard to understand it unless you see it in the game.
Go Nintendo wrote:Investigative Report from the Squid Research Lab. The protagonist, wearing the Hero Suit, travels through this underground world. The Octopus Army Corps, hoping to invade the Squid's world, built this underground facility. Is it just me that feels the Octopus' longing for the world above-ground from the blue sky projected onto those large monitors?
Link
The story sounds cool but, it's hard to understand it unless you see it in the game.