Ben's secret identity is revealed to the entire world, and he is now a superhero loved everywhere by kids and teenagers, but distrusted by many adults. Kevin and Gwen find out who revealed Ben's secret and where he lives, and the three go to "pay him a visit". The informant turns out to be a young boy named Jimmy Jones, who has followed Ben's exploits ever since he was ten-years old. With Jimmy's help, Ben and company discover a series of alien attacks in Florida. The unknown alien steals a nuclear device from a prototype interstellar rocket. They follow the alien to his ship, which he intends to launch using the nuke, which would destroy central Florida. Ben fights him as Spidermonkey, but proves to be too strong for him, so Ben turns into Ultimate Spidermonkey, with the Ultramatrix, defeating the alien with ease. Once defeated, the alien, named Bivalvan, reveals he is from the Andromeda Galaxy who was kidnapped by an alien named Aggregor. He is left restrained, with assurance that the Plumbers will be along to bring him back home. Ben reluctantly returns to school with some encouragement from Julie. The students greet him with applause, including his old bullies Cash and JT. Meanwhile, Bivalvan is found and recaptured by Aggregor.

Ben needs to be in three places at once: 1) He has to fight the Forever Knights with Kevin, 2) go to Julie's tennis game, and 3) see the Sumo Slammers movie. Using Echo Echo, he divides himself into three copies and transforms back into human form, creating three of himself. However, each is one part of his personality: one is logical, one is sensitive, and one is immature and insensitive. The sensitive Ben goes with Kevin to the museum, the insensitive Ben stays to watch Julie's match, and the logical Ben goes to see Sumo Slammers. Insensitive Ben proceeds to embarrass Julie while sensitive Ben cannot properly fight. When the Forever Knights steal a Toltech Battle Armor, Ben calls in his other selves for assistance, only to quickly realize that none of them are good fighters alone. He recombines into one and uses Lodestar separate the armor, destroying it. Ben tries to apologize to Julie, which she almost accepts, until he admits he already went to see the Sumo Slammers movie when she suggests they go see it. Furious with Ben, Julie storms off with Gwen and Kevin right behind her leaving him alone to repent for what he has done in order to gain back their trusts.

Ben's enemies are targeting his parents now that he's famous. Max, unable to deal with them alone following a fight with Sevenseven, has to enlist Ben's aid. Vulkanus, Charmcaster, and Zombozo try to attack Ben's dad, Carl, but Ben, Gwen, and Kevin intercept them. Realizing that, as a team, Ben and his friends are too strong to beat, Zombozo decides to divide and conquer. He kidnaps Ben's mother, Sandra, knocking out Gwen who tried to protect her, and hides her in a carnival to lure the team out and separate them, but Ben and Kevin manage to beat Vulkanus and Charmcaster, respectively, with Ben using Ultimate Big Chill. Gwen is left to fight Zombozo, and briefly uses her Anodite form to scare him into leaving their families alone and to spread the word to every other villain.

Ben's celebrity status lands him in a starring role in a video game. Using motion capture technology, they record the moves of his various alien forms to integrate them into the game. In reality, however, the video game offer is a ruse by TV reporter Will Harangue and his assistant Oliver as part of his plan to create a robot to defeat Ben. After defeating Ben twice and trashing his reputation, Harangue challenges Ben to a final showdown on live TV. Unable to defeat the robot conventionally, Ben realizes what Harangue has done and uses Nanomech, the one alien he couldn't get data on, to destroy the robot from within.

A turtle-like alien is causing a rampage in Bellewood. After managing to draw Ben out, who uses Ultimate Big Chill against him, and once Gwen convinces them to use the translators in their badges, he explains that he determined this to be the easiest method of finding Ben. The alien, named Galapagus, tells of how he escaped from Aggregor alongside four other aliens: Bivalvan, P'andor, Andreas and Ra'ad. Aggregor kidnapped them in a plot to permanently absorb all of their abilities. Though the aliens escaped from Aggregor's spaceship, they crash-landed on Earth. After Ben's Ultimatrix scans Galapagus' DNA, he arranges for the Plumbers to get Galapagus back to his home planet. Unfortunately for Galapagus, Aggregor was impersonating the Plumber, and recaptures him.

P'andor (one of the aliens who were captured by Aggregor) offers a huge cash reward to anyone who can break him out of his containment suit. Kevin decides to take the job, only to back out upon learning that P'andor is highly radioactive. Ben tries to stop them as Ultimate Humuongosaur, but he manages to escape. Since Kevin has the ability to open the suit using his Osmosian powers to absorb Taedenite, P'andor tricks him into cutting it open. Free from his containment, P'andor begins feeding on all the energy he can find, making his way to a nuclear power plant. Ben uses Ultimate Cannonbolt and with Kevin's help is able to trap P'andor back inside his suit, and deliver him to a pair of Plumbers who offer to take him back to his home world. Unfortunately, Aggregor intercepts the Plumbers' ship in space and recaptures P'andor.

When Ben, Kevin, and Gwen investigate an odd string of thefts by the Forever Knights, they learn that Argit is using Andreas (one of the aliens who were captured by Aggregor) to frighten the Forever Knights into making him their leader. Argit's plans go bad when the Forever Knights eventually revolt, and throw him into a dungeon with Ben and the others. When they discover that the Knights plan to execute Andreas, they break out and save him. As a last act of spite, Sir Dagonet sets a bomb that will destroy everything within five miles. Andreas sacrifices himself to absorb the force of the explosion. Although Ben and company believe him to be dead, Andreas survives and recaptured by Aggregor.

After ambushing Ben at his house, Ra'ad (one of the aliens who were captured by Aggregor) after a short fight is thrown into a pool by Jetray. Electrocuted, he awakes in Los Selodad and blames Ben for letting Aggregor recapture the other four aliens. Aggregor has been tracking them through the Ultimatrix as a homing beacon each time it scans one of them. While trying to resist being scanned by the Ultimatrix, Ra'ad causes it to malfunction, and puts himself inside it, trapping both his and Ben's consciousnesses in the same body and turning off the Ultimatrix when Aggregor comes to capture Ra'ad, and Gwen teleports them away after a brief fight. Despite Ra'ad's protests, Gwen and Kevin reactivate the Ultimatrix, and separate them. In doing so, they alert Aggregor to their location. Ra'ad flees, leaving the others to be wiped out by the Osmosian. After Kevin scolds Ra'ad for his cowardice, he decides to surrender himself to save Ben, and is recaptured by Aggregor. After the battle, Ben swears that he will do whatever it takes to save the captured aliens.

Ben saves actress Jennifer Nocturne from a group of thugs and she is immediately smitten with him, much to Julie's chagrin. However, Ben's only interest is in Captain Nemesis, Ben's hero, who shows up moments after Ben defeats the thugs. Nemesis was actually responsible for hiring the thugs, having hoped to boost publicity by rescuing Jennifer. He tries again by releasing a group of dangerous robots led by Computron, only to be upstaged by Ben. After Ben casually comments on having defeated more of the robots than Nemesis, Will Harangue twists his comments into doubts about Nemesis' abilities. Nemesis decides to hold a friendly test of skill between them, and Ben again comes out on top. Finally pushed to the edge, he captures Julie and Jennifer, daring Ben to try and save them. Ben rescues Julie while leaving Jennifer to Kevin and Gwen, then defeats Nemesis (now calling himself Overlord). Overlord is arrested, while Gwen is quick to discourage Jennifer from getting close to her most recent male rescuer. Will Harangue reports about Captain Nemesis' actions stating that a good man did bad things in order to stop "the menace that is Ben Tennyson."

With all five aliens in his possession, Aggregor tries to return to his home planet Osmos to absorb all of their powers, but a Plumber ambush damages his ship, so he instead heads for Los Soledad in order to use Paradox's time machine as an alternate power source. Despite Ben, Kevin, Gwen, and Grandpa Max's best efforts, Aggregor succeeds in absorbing the aliens' forms and powers, turning himself into an unstoppable amalgam of the quintet: Ultimate Aggregor.

With his new powers, Aggregor easily defeats Ben and his friends. Azmuth tells Ben that Aggregor intends to steal the Map of Infinity, a complete map of the entire universe. With it, he'll be able to find the Forge of Creation, the birthplace of the universe. He further explains that Aggregor stole the five aliens' powers to protect him from the traps guarding the map, which was split into four pieces by Professor Paradox. In order to keep him from assembling the map, the team tries to take the first piece of the Map of Infinity first, which is at Mykdl'dy (Big Chill's home planet). After a battle with the Necrofriggian guards, they go through the temple that houses the piece, getting past the traps, but are unable to retrieve the piece after Ben (as Fourarms) and Kevin are holding a door up, and Gwen is knocked out by a poison spike. Aggregor appears and thanks them for disabling the traps for him, and in a boost of anger, Ben holds the door himself, allowing them to escape.

Cash and JT start a TV show with Oliver (who was fired by Will Harangue after what happened in Video Games) as their cameraman, in which they claim to be the brains behind Ben's success as a hero. Ben, Gwen, and Kevin agree to play along after a sob story from the duo. Monitoring the broadcast, Vilgax's former assistant Psyphon is convinced the boys are responsible for his master's defeat and decides to kill them. During a mission to recover a Power Decoupler from the Forever Knights, Psyphon attacks, having augmented his abilities with Vilgax's technology and unleashes some R.E.D.s (Robotic Extermination Devices). Cash and JT are forced to admit their duplicity on camera to save themselves, so Psyphon turns his attention back to Ben. Ben cannot overcome him, even as Ultimate Spidermonkey, so Cash gets the idea to use the Power Decoupler on Psyphon, draining his power. Ben then knocks him out. Unfortunately for the duo, their act of heroism goes unnoticed, the weapon having knocked out the camera before firing, and their earlier confession has alienated their fanbase. Oliver leaves telling the boys that the show is over.

Ben, Gwen, and Kevin travel to the water planet Pisces (Ripjaws' home planet) after learning that Aggregor is on the planet. Aided by Magister Pyke, they travel to the planet's core, which contains a gravitational multiplier holding the water planet together. Aggregor steals the device, which is actually a disguised piece of the Map of Infinity, and escapes, causing the inhabitants to turn on Ben, Gwen and Kevin. To save the planet from floating into space, Ben transforms into Goop and uses his Anti-Gravity Multiplier as a replacement. Goop is atomized into the water of the planet, allowing him to draw all the lost water back in. With Pisces back to normal and their ship repaired, Ben, Gwen, and Kevin return to Earth.

Gwen, Ben, and Kevin follow Aggregor into a mystical dimension called Legerdomain with the help of Charmcaster, who was born there. They believe Aggregor's target to be the Alpha Rune worn by Addwaitya, ruler of Legerdomain, which they suspect is a disguised piece of the Map of Infinity. Gwen and Charmcaster work together several times, and the two develop a bond that seems to lead to Charmcaster changing her ways. While the group tries to steal the Alpha Rune, Aggregor uses the distraction to knock Addwaitya out and take it himself. Gwen, Ben, and Kevin escape Legerdomain with Charmcaster's help, but Charmcaster remains behind to free Legerdomain and her people from Addwaitya's rule. Ben promises Gwen that they will find a way to return and help Charmcaster after Aggregor is defeated.

Azmuth, displeased by Ben's failure to protect the first three pieces of the Map of Infinity, teleports Ben, Gwen, and Kevin to the fourth piece's location: a deadly artificial planet known as Perplexhahedron, created by Professor Paradox to destroy anyone who enters it. Ben, Gwen, and Kevin manage to fight their way through the traps. They are separated, and Gwen encounters Aggregor, but he simply leaves her in a freezing room, after which Ben and Kevin find her. They reach the Sentinel, who gives them the final piece. When the piece is taken, the whole planet starts to fall apart. The Sentinel stays behind, content that he has fulfilled his purpose in life, but Ben insists on rescuing him. However, Aggregor has found the Sentinel by the time Ben returns, and in the ensuing battle manages to take the final piece of the map from Ben, because he carried it back with him and dropped it. After getting back to the ship, the Sentinel, dismayed that his life amounted to nothing, vanishes into thin air. Though they've lost the battle, Kevin assures Ben that the war isn't over.

Azmuth is upset with Ben, Gwen, and Kevin for letting Aggregor get all of the four pieces of the Map of Infinity. Ben resolves to become Alien X to get Bellicus and Serena to cooperate. When this fails, Paradox arrives and changes Alien X back to Ben. After a brief argument, Paradox and Azmuth explain that the Forge of Creation is where all Celestialsapiens (Alien X's race) are born, and Aggregor hopes to absorb the powers and abilities of a newborn Celestialsapien and become omnipotent. Paradox takes them to the Forge of Creation, where an accident pulls Ben's ten-year-old self out of the timestream. After a few difficulties, past-Ben teams up with his future self to stop Aggregor. As they make their way through the Forge, they discover many Celestialsapiens in debate with themselves, and eventually a Celestialsapien egg. Aggregor reaches the egg at the same time the group does and takes everyone out with ease. In a last-ditch effort, Kevin absorbs energy from present-Ben's Ultimatrix, but the process drives him insane. He is now mutated like his old self, but has the new aliens instead of the old ones, becoming Ultimate Kevin. Kevin easily defeats Aggregor before absorbing his stolen power and attempting to kill him, only to be met with opposition from Gwen and both Bens. Past-Ben manages to get through to Kevin, who spares Aggregor's life before flying away, claiming he will not be so merciful tomorrow. Paradox arrives at that moment to take them home before the other Celestialsapiens wake up, since he is not supposed to be near them, and return past-Ben to his own time period. Paradox claims that past-Ben will dismiss the entire experience as a dream while present-day Ben resolves to stop Kevin.

With Kevin having absorbed the Ultimatrix's aliens and gone back to his insane state, he returns back to the Null Void prison, Incarcecon. Ben and Gwen, searching for answers, realize they have to go to Incarcecon in an attempt to stop Kevin from killing the warden, Morgg. There are also flashbacks that Kevin has, how he left his first mutation and started to absorb solid matter both with the help of a fellow inmate named Kwarrel, and showed how he escaped from the prison, with Kwarrel sacrificing himself to Morgg in the process. Ben and Gwen soon realize that Morgg is forcing the prisoners to mine a blue substance which is sold as a hallucenagenic drug. Kevin manages to catch up with Morgg to exact his revenge, dropping him in an elevator and cutting the line. Gwen saves him and take him into custody, but by the time they hit surface, the prison is in ruins. Kevin has fled the prison, and Ben thinks that Kevin may have to be put down, much to Gwen's shock and horror.

Argit travels to Earth to borrow supplies from Kevin for a scam, where he discovers Kevin's condition and is nearly killed by the insane and vengeful Ultimate Kevin. Ben and Gwen send Argit to the Plumber's Academy to protect him from Kevin. While there Argit meets up with the Vreedle brothers (this particular set is training to be Plumbers to avoid being assasinated by their father again), where he explains that their father sent him there to rig their grades. Kevin then goes to the Plumber's Academy to kill Argit. Ben battles Kevin but cannot defeat him. Rhomboid then launches a nuclear bomb, which will destroy the Academy and everyone in it, but Ben uses Ultimate Echo-Echo to destroy the bomb. Kevin attacks Argit and seemingly kills him. When Gwen tries to stop Kevin, he attacks her, but does not kill her because of what she used to mean to him, suggesting there is hope for him still. After Kevin leaves, Ben reveals Argit is simply pretending to be dead (as his species can temporarily stop their pulse) and Argit is arrested by the Vreedle Brothers by the order of Magister Colonach.

After Kevin absorbs the powers and abilities of Alan, Helen, Manny, Pierce, and Dr. Vicktor, Ben and Gwen argue about the best way to deal with him. Ben decides to kill him, while Gwen argues that Kevin can still be saved. The argument escalates into a heated battle between the two first-cousins, which Ben wins as Way Big using an incredibly strong and powerful cosmic ray attack. He then starts looking for Kevin, attacking anyone who has ever had any criminal connections with him, including the Forever Knights and Vulkanus. Gwen, looking for an alternative, tracks down Darkstar. She convinces Darkstar to help Kevin, and in return, she gives him enough mana to retain his normal appearance for one year. Together with a newly matured Cooper, Darkstar devises a plan to save Kevin using a fragment of the Dominus Librium. He and Cooper build a machine in Los Soledad, using the left over pieces of both Aggregor's matter energy converting device, and Professor Paradox's time machine, to strengthen and amplify the piece's energy-draining abilities, thus restoring Kevin's sanity.

Darkstar also devises a plan to have Kevin absorb a fraction of Gwen's magical and Anodite powers and abilities so that he will hunt her looking for more. The first bit of the plan is a success, but Cooper and Darkstar need more time to finish the machine, so Ben recruits his remaining allies, Grandpa Max, Julie, and Ship, to help hold him off. After a long standoff, Ben is able to use Ultimate Echo Echo to finally subdue Kevin and hook him into the completed machine. The machine restores an exhausted Kevin to normal. Suddenly, Darkstar uses the machine to drain the powers and abilities from Kevin into himself, glowing with god-like power. Predicting this outcome in advance, Ben hits a kill switch on the machine that takes all the stolen powers from Darkstar, and gives them back to their rightful owners, in the process of returning Bivalvan, Galapagus, P'andor, Andreas, and Ra'ad to life. Ra'ad thanks them. Kevin and Gwen kiss. Then Kevin apologizes to Ben for his actions, and offers him a ride to Mr. Smoothie's to get a smoothie.

Ben, Gwen, and Kevin go out into the wilderness for a camping trip. During a car race between Ben and Kevin, a strange pod falls from space. While trying to open the pod, Gwen cuts her hand on it. The pod then opens to reveal a beautiful naked blonde girl. Gwen gives the girl some of her spare clothes and the girl reveals her name to be Eunice, though she doesn't remember anything else. As the camping trip continues Eunice is revealed to have a strange connection to nature and Ben begins to have romantic feelings for Eunice (Note: Julie broke up with Ben between Seasons 1 and 2). Sunder then arrives on Earth on a mission to find Eunice. While Ben tries to take Eunice to see the ravine, Sunder appears and Ben and Eunice are separated. Ben, Gwen, and Kevin find Eunice at the ravine where Sunder activates a button on her neck, which turns her into a cylinder-like device (presumably an Omnitrix core). Ben stops Sunder from escaping with Eunice and Kevin returns Eunice back to her human form. As Eunice interrogates Sunder about her past, Azmuth appears and tells them that Eunice is really one of his early prototypes of the Omnitrix, known as the Unitrix, and that Sunder was freed from the Null Void by him to retrieve the Unitrix for him. Ben convinces Azmuth to not put Eunice into storage but to instead put her on Primus.

Baz-L is on a distant planet where he is stealing some valuable gems from some statues. Later, the statues seem to come to alive, and attack Baz-L. Ship suddenly hears Baz-L's cries for help, and leaves Julie to help his old owner. Julie ask Ben for help to locate Ship, who left to help Baz-L. However, their break-up makes things difficult, but Gwen and Kevin agree to help Julie. Ben realizes his mistake, so he transforms into Jetray and flies into space to chase after the Mecha-Vehicle. Gwen, Kevin, and Julie find Ship. Ship refuses to go back to Earth without saving Baz-L first. Ben arrives on the planet. Kevin tells Ben that the reason Julie broke up with him was because he was being a jerk. Soon they reach Baz-L, who is still being tortured by the one-eyed aliens to reveal the location of their precious artifact, the Occulent. The Sentinels, the statues, awaken and attack Ben and others for the Occulent. But it is revealed that Baz-El had eaten Occulent, so Julie gives it back to the Sentinel and they go back to their stationary positions. Julie then gives Ship to Baz-L, saying that Ship would be happier with him. However, Ship decides to remain with Julie. Ben apologizes to Julie for being such a jerk and promises to make it up to Julie by trying to be a better boyfriend.

Zarcovia's soldiers has found the frozen body of Dr. Viktor. Prince Gyula and King Xarion want to see this weapon, Gyula wants to control Dr. Viktor to use him against rebels in their civil war, but Xarion tells him not to, King Xarion asks for help from Ben, Gwen, and Kevin and explains what Gyula is trying to accomplish. When they find Dr. Viktor's corpse, they are found by Gyula's soldiers, while fighting them, Dr. Viktor's ice block begins to melt and he breaks free, Gyula reveals that Dr. Viktor is under his control, Dr. Viktor defeats Ben, Gwen and Kevin and imprison them, along with Xarion. Gwen manages to free Xarion, but he takes an unconscious Ben for his own plans. He conducts an experiment on Ben using AmpFibian, Dr. Viktor, and himself, but Prince Gyula interferes in order to stop Xarion from taking control of Dr. Viktor, unfortnantly King Xarion's mind has been transferred to Dr. Viktor's body King Xarion, now calling himself King Viktor, starts hurting Prince Gyula. He releases Gyula as a last act of mercy, and starts atacking the rebels, but was defeated by Heatblast and Gwen and Kevin. Gyula and his soldiers try to take King Viktor back, but Ben takes Gyula's device that controls his soldiers and sets them free. And King Viktor swears to Ben to take revenge.

Jimmy Jones is looking for the biggest new story he and Ben can tackle, but thats when he stumbles upon a strange pink tentacled creature which crashed from the sky into a near by cave.

Gwen is excited by the prospect of her cousin Sunny paying the team a visit while dealing with the Robots of Dimension 12. But her excitement quickly turns into trepidation when it is uncovered that her cousin is not all that she appears and has some particularly sinister intentions.

Victor Validus resurfaces and attacks Ben at night. Elena Validus and the nanochips return.^[2]

An evil creature has plans to enslave humans after his accidental release by the Forever Knights led by Sir Reginald. Ben, Gwen and Kevin have an encounter with Sir Cyrus (who claims that his faction is the true path from the ones led by Patrick, Urian, and Driscoll) who blame them for releasing the creature until one of the Forever Knights stated that Sir Reginald was responsible.^[3]

TBA