Following the Gokaigers' defeat at the hands of Basco, Warz Gill permits Damarasu to send down Action Commander Shieldon to eliminate the pirates while they are weakened. As Ahim tends to Gai's broken arm aboard the Gokai Galleon, Captain Marvelous, Joe, and Luka work on refining their fighting skills and Doc attempts to develop a new weapon to help his shipmates. Later, on his way from picking up some take-out food, Doc meets a struggling teenage boy practicing his soccer skills so he can be put on the team for their next game. Inspired by the boy's determination, Doc wishes the boy good luck before heading back to the ship to continue his engineering work. The next day, Gokai Green tests out his modified Gokai Gun, which has an additional Gokai Cylinder built onto it, when he is ambushed by Shieldon and his troops. The other four Gokaigers arrive on the scene to dispatch the Gormin, but Shieldon proves himself to be invincible by using his Thick Face Shield to deflect their Gokai Slash attacks, along with the finishing attacks of J.A.K.Q.'s Big Bomber and the Dynamen's New Super Dynamite. Gokai Green's modified Gokai Gun also proves to be ineffective against the shield as its Gokai Cylinders explode from the strain, forcing the Gokaigers to use the Kakuranger Keys to escape. Later, depressed by his failed project, Doc returns to the park to find the boy also depressed at the fact that he did not make the starting lineup. While restoring the boy's confidence and practicing with him, Doc is again inspired when boy mentions that teamwork is important for a team to win. Returning to the Gokai Galleon, Doc asks his shipmates for their weapons to create a better weapon. Captain Marvelous and the others give Doc their gear so he can get to work despite his warning that there is a risk that they could be attacked by the Zangyack Empire while unarmed. As feared, Shieldon and his Zugormin attack the Gokai Galleon the next day. While four of the main Gokaigers fend off the attackers, Doc tries to quickly finish the weapon before Gai points out that the weapon's frame resembles the Ohré Bazooka. With that realization, and remembering Goro's parting words to them of using his team's power for such a crisis, Doc uses the Ohranger Keys to infuse the Ohrangers' Great Power into his weapon. Gokai Green enters the battle with the newly-completed weapon, christened the Gokai Galleon Buster, and the Gokaigers vaporize Shieldon with its Rising Strike attack. Shieldon is revived by the growth beam, prompting the Gokaigers to form Hurricane Gokaioh and fight the shieldless Action Commander. Despite his injury, Gokai Silver joins in the fight with Goujyujin before Hurricane Gokaioh destroys Shieldon. Later, the boy tells Doc that despite not making the starting eleven, he will continue to work hard to make the field next time. The rest of the crew notice that Doc is noticeably more confident than usual, as he has accomplished what he set out to do this time. Captain Marvelous, however, reminds Doc to re-attach the Gokai Cylinders back into their other weapons.