Hajime Ichinose is a rather eccentric schoolgirl who is obsessed with notebooks. One day, she is approached by a mysterious man named J.J. who pulls out a journal called a NOTE from her body, declaring her to be the new member of the elusive Gatchaman team.

The mysterious "Crowds" are revealed to be strange beings controlled by the GALAX users. Meanwhile, Joe fights against the strange alien known as Berg Katze, but is beaten back when Katze uses a NOTE of their own.

Katze takes on Rui's form to steal control of GALAX and form a new "Hundred". Hajime suggests the best way to fight is for the Gatchaman team and Rui to reveal themselves and go public. Rui learns a troubling fact about the side effects of Crowds.

Rui regains control of X, and uses the GALAX network to help the Gatchaman team in the crisis. Hajime convinces the Prime Minister to broadcast a message on the Gatchannel, asking everyone to join the GALAX network and band together. But Katze takes the form of the Prime Minister, once again urging people to use Crowds.

Misudachi Tsubasa is an ordinary high school student in Nagaoka City. But everything changes when an alien spaceship lands crashes down right next to her house and the Tachikawa Gatchaman crew come to investigate...