The Tragic Mach 3.5 Operation

Joe and the professor go to the presentation of a new civil aircraft called Mach 3.5 designed by a brilliant Japanese scientist, Prof. Doyama. The aviation managers decide to entrust the new vehicle to Joe, who will become its first pilot. The Gailarians, hearing the news, decide to kidnap the professor to take possession of his creation. Joe, on reconnaissance with Kaori, Professor Doyama's daughter, discovers the alien attack but too late. The professor has disappeared and the boy ends up in an ambush by two alien soldiers who also manage to kidnap the hostage's daughter. The Gailarians also manage to recover the missing element, i.e. the superfuel necessary for the operation of the Mach 3.5. Rita goes into action with little Tobè who, driving the auxiliary drill of the Groizer X, recovers Joe who manages to destroy the enemy plane.

O Prof. Toyama, criador do avião Match 3.5 MJ se torna refém dos gailarianos, que querem roubar seu avião e torná-lo um cientista de Gailar. Para pressioná-lo, seqüestram sua filha, o que Joe tenta impedir sem sucesso. O professor, se vendo na impossibilidade de reagir, parte com seu avião sob as ordens de Gailar, mas atira-o em direção ao solo, preferindo a morte a entregar o Match 3.5 a Géldon.