The Boonboomgers and HIKAKIN are filming a collaboration at a circuit purchased by Taiya Hando, when suddenly a princess from the planet Trickle escapes! The Boonboomgers protect her from Demon Thunder, the Catching Captain, who threatens to launch a planet-destroying missile at Earth if the princess is not handed over! The power of Demon Thunder has transformed the circuit that Taiya bought into the Circuit Grumer, and what's more... The usually reliable Boonboom Cars have also been swallowed by Circuit Grumer, and are now under his control!? The unpredictable situation puts the Boonboomgers in a big pinch!

Nicola, who has been crowned queen of the planet Trickle, has decided to form an alliance with the planet Chikyu. The Bakuage Sentai Boonboomger were invited to witness the event. However, a remnant of the Hashiriyan, Manhole Grumer, suddenly appears and steals the jewel of the Trickle royal family from Nicola. Furthermore, Minongan, one of the Uchu Five Jesters, also appears and steals the holy sword OhgerCalibur ZERO, which had been prepared for the ceremony of the alliance. The King-Ohgers rush to the scene and fight alongside the Boonboomgers, but the warriors are separated by the mysterious power of Manhole Grumer. Scattered across the stars, the King-Ohgers begin their own actions to escape their predicament. Soon, a dangerous heartbeat begins to echo from the depths of the earth. When a powerful malevolence is about to awaken, will the two great Super Sentai be able to come together again and fight together? The battle for the three stars begins now...!

The special tells the universe-spanning tale of the Settler duo, Sakito Homura and Byun Diesel, before their return to Earth after over a decade of absence.