Sometime prior, amidst the Legend War, the Goseigers and Gosei Knight are overwhelmed by the Zangyack Empire's first invasion force until they are saved by the Gorengers and J.A.K.Q.

As the depowered Sentai teams regroup and part ways, Aka Red, having seen the Legend War from space, goes on to collect the powers, turn them into Ranger Keys, and contribute to the Gokaigers' formation.

While the Zangyack forces retreat, the Goseigers demand Gosei Knight's key, but the Gokaigers, unaware that they have it, refuse to listen and withdraw.

As Warz agrees, the Gokaigers familiarize themselves with the Sixth Hero Ranger Keys they recently acquired[a] before the Goseigers use their mecha to attack them.

Taking advantage of their weakened states, the Black Cross King enlarges himself, but the Sentai teams are suddenly engulfed by a bright light, during which representatives of the J.A.K.Q.

On the ground, the Goseigers' ally Nozomu Amachi urges Tokyo's citizens not to give up hope and cheer for the Sentai teams.