Pinwheel Power Plant is the twenty-fourth mission in Splatoon's single-player mode, Octo Valley. It is named as such because of its heavy use of Pinwheels.
Why are we here? For what purpose do we exist? We must not dwell on these questions. We can merely trust in the will of the universe and spend our days and nights in harmony with the world, celebrating this festival called Life.
Location: At the second checkpoint on the floating platform to the left of the second pinwheel. When you arrive at the second checkpoint go down the drop and up the wall to get to the second pinwheel. Splat the Octotrooper and ride one of the spinning platforms to jump across to the floating platform and get the scroll. It should be noted that the jump can only be made in squid form. Behind it is a Lanchpad to take you the other platform.
Pinwheel Power Plant Final Checkpoint-Another Enemy Octotrooper
Pinwheel Power Plant Final Checkpoint-Enemy Octotroopers
Trivia
175This mission's subtitle is a pun on "defences" and "the fences", referring to the grates on some pinwheels.
In the Europe and Oceania version of the game, one of Agent 1's quotes during Pinwheel Power Plant has a typographical error: when Agent 3 picks up one of the InkzookaCanned Specials, she will say "Inzooka!".
This mission is the only mission to feature Shielded Twintacle Octodivers.
Zapfish is...up there.
to 
dash jump over the beams.
