In the city, the Rangers slowly awaken from the recent attack. Antonio stands up to find the Barracuda Blade and the injured Deker. Antonio prepares to finish off Deker to prevent him from taking part in Serrator's plan. He controls the urge and leaves the scene.
At the Shiba House, the Rangers discuss the recent events. The Sanzu River is erupting from the six locations. The barrier between the human world and Netherworld is growing weaker. Antonio apologies for not taking the opportunity to defeat Deker. His friends tell him that he was noble for not attacking Deker when he was unable to defend himself. In the forest, Deker remembers Serrator's words. Dayu follows Deker to the remains of their old home. Deker is uncertain on why he came to the location. She asks if Deker feels anything. Deker responds that he feels nothing and leaves the forest. Dayu has a brief flashback when Deker became a Nighlok. Back at the Shiba House, Mike and Kevin find Antonio's note on the Lightzord. Antonio leaves the note saying that he knows what he must do. As they are about to follow Antonio, the Gap Sensor alerts the Rangers to battle. Jayden orders the Rangers to split up to find Antonio and deal with the Gap issue. Bulk and Spike stand in front of the Energy Beam. Bulk tells Spike that this is their chance to become true Samurai. Spike's annoying chewing gives him the idea to block the beam with bubble gum. Bulk and Spike head back to the Garage to find Spike's collection of gum, which he bought in bulk. Bulk and Spike begin chewing the gum. Serrator enjoys his recent victory and awaits Deker in take his place. Deker walks down the road until he runs into Antonio, who challenges him to a fight. Serrator wonders why it's taking Deker so long. Jayden, Emily, and Mia head to Serrator's location. Serrator fires a blast towards the Rangers, who morph into action. The Rangers face off against the Moogers. Kevin and Mike continue their search for Antonio. Antonio is unable to fight Deker. He tries to reason with Deker, who attacks him. Mike and Kevin arrive in time to protect Antonio. Mike yells Antonio's qualities as Deker leaves the scene.
Bulk and Spike continue their mission of chewing gum. The gumball is almost the size of them. The Rangers defeat the Moogers. Red Ranger powers up to Super Samurai Mode and turns his attention to Serrator. Deker enters the scene and approaches Serrator, who is pleased to see him. Serrator blasts the Rangers to the ground. He gives Uramasa to Deker and orders him to split the world. The rest of the Rangers arrive to the scene. Super Samurai Red Ranger fires the Super Bullzooka towards Deker. Serrator blocks and reflects the attacks back to the Rangers, who are powered down by the blast. The Rangers watch as Deker raises the sword. He rapidly turns around and attacks Serrator. Deker explains that he only cares for the sword, not the hatred for humans. The energy beams restore back to normal. Bulk and Spike push the gumball over the nearby energy geyser. The beam stops right before they place the gumball over the hole. Bulk and Spike celebrate their victory. Serrator uses the last of his energy to fire a series of massive attacks towards the unmorphed Rangers.
Deker tells the Rangers to finish off Serrator. The Rangers morph into action and form the 5 Disc Octo Cannon. Serrator slowly walks towards the Rangers as they fire the Octo Cannon and Super Bullzooka attack to defeat him. Serrator grows to his Mega Mode. The Rangers form the Megazords: Samurai Megazord, Bull Megazord, Claw Battlezord, and Light Megazord. Serrator summons two Papyrux Nighloks. The megazords work together to defeat the Papyrux Nighloks. Light Megazord and Bull Megazord concentrate on Serrator. The Rangers form the Samurai Gigazord. Serrator attempts to attack the formation, but his attempt fails. Red Ranger powers up to Shogun Mode. The Samurai Gigazord fires the finishing attack towards Serrator, who pushes the attack back. Serrator is the first Nighlok to withstand the Gigazord's attack. Gold Ranger mentions that there is one final zord: Shark Zord. Shogun Red Ranger summons the Shark Zord to form the Samurai Gigazord with Shark Sword. Serrator fires a series of attacks towards the Samurai Gigazord. The formation charges the Shark Sword with all of the symbol powers. The Ultimate Samurai Slash attack finally defeats Serrator. In the forest, Dayu confronts Deker about his decision. Deker responds that he will end his curse on his own terms. He feels that there is some connection with Dayu. The Rangers celebrate their victory. Antonio ponders about Deker's choice. Rangers Together, Samurai Forever!