After Messiah's first defeat, the Go-Busters are surprised to be alerted to the appearance of a strange energy in the city. When they investigate they find a robotic woman named Shelly who says she is the partner of Space Sheriff Gavan. After Ryuji, Yoko, and Shelly are sucked into Makuku Space, Hiromu must team up with Gavan to stop Rhino Doubler from causing trouble in the city.