Amelia struggles with fulfilling her Ranger duties and helping Fairview and her android assistant, J-Borg, with a video tour while the other Rangers try to locate Rafkon. Meanwhile, Slyther and Mucus receive word that Void Knight is alive from Sporix Beast Bitscreem, who attacks the Rangers and steals their Fix-it Dino Key. Suspecting Void Knight may be still alive, the Rangers re-examine security footage of Bitscreem and a disguised Slyther. Realizing Bitscreem was spying on them, the team attempts to destroy Void Knight's sword, but Amelia gets distracted by her job and the plan fails. As such, Zayto forms the T-Rex Cosmic Megazord to defeat Bitscreem while the others drive out the other enemies, though Void Knight makes off with Bitscreem's Sporix. Afterwards, Amelia learns that Fairview and J-Borg's footage was destroyed, leaving her free to focus on her Ranger duties while Void Knight repairs his armor and resumes his plans.
Having survived his previous encounter with the Rangers, Wreckmate returns to Void Knight and competes with Slyther to see who can defeat the most Rangers, with Wreckmate stealing a potion from Slyther to help accomplish this. Meanwhile, the Rangers are celebrating the Triple Sun Festival, a Rafkonian holiday, during which Aiyon receives a motorcycle while Zayto receives "Dino Chucks". However, as the others leave to cook for the event, Aiyon secretly plays with the weapon and breaks it, allowing Wreckmate to defeat the Rangers in battle later on. They check the Legendary Ranger Database for inspiration on a new weapon, but are short on supplies to make one. Aiyon, making good on his earlier mistake, offers his motorcycle, which Zayto and Solon turn into the Dino Fury Cycle, which Zayto uses to defeat Wreckmate once more, forcing the enemy to retreat. Afterwards, the Rangers resume their festivities.
A Sporix Beast named Occulo joins Void Knight's group in finding the remaining Sporix while the Rangers continue searching for Rafkon. Izzy and Javi find a Sporix, but Occulo overpowers and outwits them both before altering their memories with an amulet and stealing the Sporix. When the Rangers return, Solon suspects that their memories were tampered with and tries to fix them, but the others decline her help. Meanwhile, Zayto heads off to find Rafkon in the T-Rex Cosmic Megazord, but only finds a beacon in space. Back on Earth, Occulo strikes again, with the remaining Rangers heading out to engage him while trying to call Zayto back to Earth. After being rejoined with Zayto, who restores his comrades' memories, the Rangers engage Occulo, Mucus, and Slyther, but Void Knight overpowers them all and leaves with a huge stash of Sporix. Afterwards, the Rangers reconcile with Solon and resume their investigations surrounding Rafkon while Void Knight orders his group to accelerate his plan's progress.
While searching for more Sporix, Occulo stumbles across the Rangers finding a tiny Zord amidst training practice. Upon learning of Occulo's discovery, Void Knight orders him and Wreckmate to take the Zord hostage in exchange for the Rangers' Sporix. In the ensuing chaos, the Zord runs away, forcing Aiyon and Ollie to find it. In the process, Solon discovers the Zord is actually the offspring of the Pacha Smash Zord. The two Rangers find it at a cliff before enlarging and freeing it while the remaining Rangers struggle against the monsters. Aiyon enters the battle and engages an enlarged Wreckmate in his Megazord, but is overpowered. Meanwhile, Ollie uses the Dino Smash Key to defeat Wreckmate and free his comrades. The united team summon and use their Megazords along with the Pacha Smash Zord to defeat Occulo, but Void Knight claims his Sporix. Afterwards, a humbled Aiyon promises to be more receptive to advice while Void Knight receives enough power to activate his machine and revive Santaura.
Void Knight, real name Tarrick, tends to Santaura, intending to leave Earth with her after she recovers. Meanwhile, Fern and Izzy prepare for their school's prom. Izzy gets a dress, much to her disgust, and dumps it when a Sporix Beast named Junkalo launches an assault on the city's dumps. The Rangers gather to fight him, but are overwhelmed by his stench. Izzy discovers her mother Rina accidentally gave her Fern's dress, which Javi finds at the dumps, now ruined. Izzy explains the situation to her mother, but the latter forgives her and the two decide to make a new dress for Fern. When Tarrick sends Junkalo to fight the Rangers again, the Rangers summon their Zords to defeat him and claim his Sporix, unaware that Tarrick has obtained the materials and data he needs for his new invention, the Zord Jammer. Days later, Fern and Izzy head off to the prom, with Izzy's friends escorting them there.
Santaura pulls a Sporix from Tarrick's machine and asks him to use it to gain more power, but he refuses. He starts to return the Sporix, but Doomsnake re-hatches from it. As Slyther finishes building the Zord Jammer, Tarrick tasks him and Doomsnake with fighting the Rangers. Meanwhile, Javi realizes the leader of his favorite band, Blair, has the Freeze Dino Key, which Zayto reveals can help them locate the missing Ptera Freeze Zord. The Rangers are called in to fight Tarrick and Doomsnake, but when Slyther activates the Zord Jammer and the Rangers fail to summon their Zords, Ollie forces the villains to retreat while the Rangers regroup to find the Ptera Freeze Zord. Javi returns to Blair and asks for the key, but the latter refuses unless Javi serves as a replacement guitarist for an upcoming show. Javi agrees, and gets the key despite earning Carlos' ire, though they later reconcile. Together, the Rangers find the Ptera Freeze Zord, fight off Tarrick's forces, defeat Doomsnake, reclaim his Sporix, and destroy the Zord Jammer. Concurrently, Santaura fuses herself with a Sporix and transforms into Void Queen.
Void Queen initiates her plan to exact revenge on humanity, summoning Sporix Beast Squashblight for the task. Meanwhile, Ollie encounters his school professor Drake Floyd, but he belittles Amelia's magnet brace, causing Floyd to call him out on his rudeness. Squashblight begins his rampage, turning people into trees by poisoning Pine Ridge's water supply with his venom and repelling the Rangers' assaults. Later, Ollie develops an antidote with Amelia and Solon, but Solon falls victim to Squashblight's venom when Ollie dismisses Amelia's warnings concerning a boiling sample while Void Queen abuses Tarrick. Amelia uses her invention to complete the antidote and cure Solon just as Squashblight resumes his attack, accompanied by Wreckmate. The Rangers attempt to engage both villains, but are overpowered until Tarrick arrives and tells them that Squashblight is susceptible to darkness as the Sporix Beast enlarges. The Rangers form the Ptera Smash Ultrazord and knock Squashblight into a thunderstorm to defeat him and claim his Sporix while Zayto cures the victims. Afterwards, Ollie apologizes to Floyd for his flippancy while his friends struggle to determine why Tarrick helped them.
Upon learning of Tarrick's actions, an angry Santaura summons Sporix Beast Trackenslash to find him. Meanwhile, a disguised Tarrick heads to BuzzBlast and overhears the Rangers discussing his trustworthiness, with Zayto believing he cannot be trusted, just as BuzzBlast is attacked by a hacker demanding their own show. The Rangers start to investigate when Solon warns them of Trackenslash's arrival, and they head out to engage him. He overwhelms the Rangers, but Santaura reminds him to focus on his mission and Trackenslash obeys. Returning to their investigation, the Rangers eventually locate the hacker, a little girl named Mara, who admits that she has always wanted to be on BuzzBlast, but is too young. Aiyon convinces her not to waste her talents on criminal pursuits and apologize to everyone at BuzzBlast. Later, the Rangers re-encounter Trackenslash, but he overpowers them once more until Tarrick arrives to help Zayto defeat the beast and reclaim his Sporix. The Rangers are still distrustful of Tarrick, who says he does not want the Sporix anymore and promises that he will attempt to recover the ones he stole to prove himself to them.
Void Queen builds a new robotic general, Snageye, to capture the Rangers while Tarrick unsuccessfully tries to steal more Sporix. Meanwhile, Amelia begins investigating a supposed ghost sighting when Solon calls the Rangers to the warehouse district. There, they meet Tarrick, who explains Void Queen's plans, her new general, and her origins, before offering to help them defeat her, though a skeptical Zayto refuses. The Rangers return to find the ghost, when Snageye attacks, trapping Izzy, Amelia, Ollie, and Aiyon in a pocket dimension while Zayto and Javi retreat to discuss Tarrick. When the two meet him again, Snageye traps the remaining Rangers, but Zayto telepathically sees Tarrick fighting Snageye and witnesses Tarrick's heroism just as Tarrick frees him and hands him the Dino Knight Morpher and its accompanying key. With the new equipment in hand, Zayto assumes his Dino Knight form, destroys Snageye, and frees his comrades, but Void Queen captures Tarrick. Afterwards, the Rangers ponder Tarrick's change of heart and Void Queen's plans while Zayto notes that people can change and the "ghost" is revealed to be a drone in a tarp.
While cycling through the forest, Aiyon and Izzy stumble across a truck from Area 62 and a case containing a strange collar and wads of cash. They argue over what to do with the money while Void Queen summons Flapnarok. Using the collar Mucus found, Flapnarok enlarges and overpowers the Rangers and their Megazords. Meanwhile, Aiyon goes on a shopping spree until he meets Pop-Pop, who reveals he lost his disco shirt and gives him advice about genuine happiness and honesty. Inspired by this, Aiyon hands his shirt to Pop-Pop and gives away his products for free while the others discuss forming the Primal Ultrazord, a dangerous Zord combination which killed Aiyon and Zayto's original comrades in the past. Aiyon and the Rangers regroup to complete adjustments to the Ultrazord just as Flapnarok strikes again. In response, the Rangers deploy and form the Primal Ultrazord to defeat the monster. Afterwards, Izzy and Aiyon reconcile, the latter having used the last of the money to get Izzy a new bike.
Javi enters BuzzBlast's song competition, but is forced to make a new song after Blair steals his original one. Meanwhile, Void Queen brainwashes Tarrick to her side, transforms him into Void King, and sends him to the city's stadium to cause chaos. The Rangers head out to engage the new enemy, but are overpowered, with all but Javi and Zayto getting injured. Back at Dinohenge, they discuss Void King's tactic of copying their moves and train against each other to find a weakness, discovering the Dino Knight Morpher's finisher can only be used once per transformation. Just then, Void King resumes his attack, with Zayto accessing his Dino Knight form to engage him solo. Using what he learned from his training, Zayto defeats Void King, forcing the latter to retreat. Afterwards, the other four Rangers show signs of recovery and Javi uses his electric guitar, harmonica, and keytar for his song, winning the competition.
During an interview, Amelia and two of her BuzzBlast colleagues receive word about a supposed Bigfoot sighting. She tries to tell Fairview about her find, but is turned down, causing the three to decide to investigate Bigfoot themselves. Just then, Solon assembles the Rangers and reveals that General Shaw contacted them to warn them of a breakout in Grid Battleforce. The Rangers are deployed to fight a monster that arrived at Pine Ridge, but are overpowered by the enemy, who introduces himself as Lothorn, Lokar's nephew. Returning to base, the Rangers struggle to determine Lothorn's purpose while Amelia's colleagues find him destroying Dinohenge's statues. The Rangers scramble to save the civilians before engaging an enlarged Lothorn, summoning their Zords to help destroy the monster. Afterwards, Amelia apologizes to Fairview while Shaw reveals Scrozzle had been freed and Lord Zedd caused the breakout.
On Valentine's Day, Ollie intends to ask Amelia to be his Valentine, but a misunderstanding ensues between them. Meanwhile, having reclaimed his staff, Zedd returns to Area 62 with Scrozzle and robotic ally Sizzurai, claiming he wants to form an alliance with Void King and Queen to conquer Earth. Using data he preserved from Boomtower and Snageye, Void King tasks Scrozzle with building upgraded versions to aid them. While they wait, Zedd and Sizzurai attack the Rangers, with the latter brainwashing Ollie to make him collect information on Rafkon. As Solon alerts the Rangers to Zedd's return, the Rangers mobilize to stop him, only to face Void King, new general Boomblaster, and Ollie. The Rangers use the Snooze Dino Key to put Ollie to sleep and bring him back to Dinohenge so Solon can cure him while Zayto and Amelia hold off their enemies until Boomblaster leaves to help Zedd, followed by a suspicious Void King. As he and Void Queen learn Zedd betrayed them and left Earth with the robots they built him, the Rangers and Solon awaken Ollie, who reconciles with Amelia before Zayto uses his telepathy on him to discover Zedd's plot to reach Rafkon.
With the information Zayto received, the Rangers finally pinpoint Rafkon's location to stop Zedd. While the Rangers head off, Zedd and his minions scour the planet for the Sporix generator, intending to use it to create their own army of Sporix Beasts. Upon arriving and eager to fulfill his duty, Aiyon launches an attack on Zedd, his new robotic general Nulleye, and the rest of their group, only for Zayto to call him out for his lack of teamwork afterwards. The Rangers continue searching for the Sporix generator using information they overheard from Zedd and his generals earlier. However, the team is ambushed by the villains after finding it. In the ensuing battle, Zayto blocks a laser attack from Zedd's staff inadvertently directing it to Sizzurai and destroying him while Zedd and Scrozzle work on the machine. Aiyon tries to engage Zedd, but is overpowered, with Zayto getting injured trying to protect him. With Zayto and Aiyon incapacitated, the Rangers are cornered by Zedd before they are suddenly teleported out of the fight. Back at Dinohenge, Aiyon laments his rash actions costing his team the mission and Zayto's health when the Green Morphin' Master appears to them.
The Green Morphin' Master heals Zayto before giving the Rangers a new weapon to fight Zedd. However, the Blue Morphin' Master stops her, warning her that she has intervened too many times. Zayto tries to defend Green's actions, citing three events where she helped past Ranger teams, but Blue is unconvinced, mentioning that their comrades were killed by new villains every time they made a new team. With the new equipment in hand, the Rangers return to Rafkon to stop Zedd, who succeeds in stealing and escaping with the Sporix generator. The Rangers narrowly escape themselves before Rafkon explodes and return to Earth to stop Zedd. Over the course of the battle, Aiyon destroys Boomblaster while Scrozzle, Nulleye, and Void King escape. With Aiyon's help, the Green Morphin' Master sacrifices herself to imprison Zedd with her in a crystal and destroy the Sporix generator. Seeing the error of their ways, the Red and Blue Morphin' Masters free her and take Zedd away while Zayto decides to make Earth his new home.
Javi tries unsuccessfully to make a music video for BuzzBlast. His friends take him for a walk in the park when they see Mucus selling wish charms. Each Ranger makes a wish, with Javi suddenly getting millions of views. However, they discover that their wishes, actually made reality by a Sporix Beast named Hexcurio, have unexpected side effects. The Rangers try to fight the monster, but his allies overpower them, forcing them to withdraw while J-Borg and Fairview discover another musician, Pete, arriving in town for a performance with Javi, leaving Javi torn between helping the Rangers break Hexcurio's spell and his performance with Pete until Lani encourages him to work hard to achieve his dreams. Taking her lesson to heart, Javi helps his allies attack the enemy. When Hexcurio enlarges, the Rangers and summon their Zords to defeat him, breaking his spell over his victims, though Mucus claims his Sporix. Afterwards, Pete and Javi perform their duet while Amelia is crestfallen over her wish to see her parents seemingly being left unfulfilled.
As Izzy learns that Fern has been accepted into college, a Sporix Beast named Quickspine suddenly attacks, forcing Izzy to leave Fern to fight him with her comrades. Amidst the battle, Izzy saves Fern and Carlos from Hengemen, but has to hide her identity when Fern confesses to her that she loves her, unaware of her true identity. Withdrawing to Dinohenge, the Rangers discuss ways to counter Quickspine's speed while Izzy worries over Fern texting her. When they meet again, the two argue over Izzy keeping secrets from Fern and Carlos chastises Izzy for turning down the college's offer, leaving Izzy lost on how to explain herself without revealing her Ranger duties. Suddenly, Quickspine attacks again, stealing Carlos's key and injuring him. The Rangers assemble to fight him again, successfully slowing him down. When Quickspine enlarges, the Rangers summon their Zords to defeat him, but Void Queen claims his Sporix and the key he stole. Afterwards, the Rangers visit Carlos as he recuperates from his injury and Izzy and Fern reconcile, the latter having deduced Izzy is the Green Ranger.
While planning a romantic getaway, Ollie neglects Lani to spend more time with Amelia until the Rangers are informed of Sporix Beast Sugarhit being sighted in Osaka, Japan. Joined by Aiyon and amidst their search for the monster, Aiyon encounters Lani, who is disappointed her son did not meet her as planned, before encountering Sugarhit. The enemy buffets Aiyon before retreating when his comrades assist him. As the others discuss Sugarhit attacking Osaka, Lani chides Ollie for remaining out of touch and neglecting his work. Later that day, Amelia and another professor also call out Ollie for neglecting his mother. Suddenly, Sugarhit strikes again. The Rangers pinpoint his location to a Japanese village and rush over to engage him. When Sugarhit escapes and enlarges, the Rangers summon their Zords to defeat him, with Ollie claiming his Sporix. Afterwards, Ollie apologizes to his mother, promising to redo his work and he and his friends continue their vacation. Concurrently, Void King and Queen and their minions try and fail to activate drill machines underground back in Pine Ridge.
As Carlos finishes work on a drill for Pine Ridge's sewage system, Void King unveils the Sporix Blaster, a weapon that can brainwash its targets. Meanwhile, Javi and Izzy try to find a new activity for their family when Solon alerts them of Wreckmate attacking the city. The Rangers transform and deploy to fight him, but Nulleye suddenly attacks them with the Sporix Blaster, hitting Izzy and Javi before Aiyon destroys the gun. The Rangers retreat to Dinohenge, where a brainwashed Izzy and Javi try to seize their Sporix chest, forcing their comrades to drive them out. Following Void Queen's instructions, the two brainwashed Rangers find out the passcode for the drills from Carlos and successfully activate them, with Void King programming them to tunnel to Dinohenge. Meanwhile, Nulleye and Sporix Beast Clawfare engage the remaining Rangers while Carlos and Rina engage in karaoke night. Zayto destroys Nulleye. As Izzy and Javi listen in, their brainwashing is undone, allowing them to rejoin their comrades and summon their Zords to defeat Clawfare. However, Void Queen claims his Sporix and Void King arrives at Dinohenge, injuring Solon and making off with the Rangers' Sporix chest.
The Rangers meet a group of Rafkonians led by Orria, who intend to attack Earth under the belief that all humans are evil. Meanwhile, Void Queen releases all of the Sporix and initiates a wide-scale assault on Pine Ridge, forcing the Rafkonians and the Rangers to work together to fight them. Zayto and Aiyon fight a Sporix Beast named Crashflood to stop him from flooding Pine Ridge while the others fight Wreckmate and other Sporix Beasts. During the fight, Fogshell tries to attack Orria, but Pop-Pop defends her, getting injured in the process. As Orria changes her mind about humans, Pop-Pop discovers that Amelia is the Pink Ranger and admits that when he worked in Area 62, he encountered a pair of aliens, who asked him to take care of an infant Amelia for them.
As Zayto and Aiyon are proud to learn from Amelia that she is a surviving Rafkonian who currently fights alongside them all along, the other Rafkonians and Rangers defeat the Sporix Beasts. However, Void Queen uses the Sporix to create a cocoon. While the Rangers fight and destroy Wreckmate, Amelia travels to Area 62 to learn the truth about her parents. Slyther attacks her, but the Rangers save her, forcing Slyther to flee. Void King attacks them, but Amelia throws herself onto him and discovers he and Santaura are her parents. Void King, upon realizing this revelation, is freed from Void Queen's brainwashing and reverts to Tarrick.
Tarrick uses the Dino Knight Key to transform into Void Knight one last time and teleport the cocoon to a desert to prevent Pine Ridge's destruction. However, Void Queen uses the cocoon to create the Nemesis Beast. As the Rangers fight her, Zayto sacrifices the Zords to weaken the beast and disappears. Void Queen attempts to kill the remaining Rangers and Tarrick, but Amelia appeals to her better nature and reveals the truth, causing Void Queen to forgo her revenge, destroy the Nemesis Beast, and revert to Santaura. The Morphin' Masters capture all but one of the Sporix in a crystal, unaware that Mucus went into hiding. Six months later, the Rafkonians make Area 62 their new home, Pop-Pop and Amelia prepare Tarrick and Santaura for the arrival of their new daughter, Mucus and Slyther have taken on human disguises and began running a circus together, the Garcia siblings become famous after Izzy’s graduation, Aiyon opens his own Rafkonian-themed cafe, and Zayto returns to warn his team that Zedd has escaped.