On their way to Pluto with materials to rebuild the damaged Base, three Star Fleet transport cruisers have mysteriously disappeared. X-Bomber is called in to escort the next transporters. They encounter Imperial Alliance warships, and destroy the alien fleet. But Commander Makara sets a trap, and as X-Bomber attacks the Alliance Base on Jupiter, Orion sends his missiles against Dr. Benn's ship. Shiro, Lee and Hercules take off, using X-Bomber's new weapon Dai-X, to destroy the alien base.