Worried that Chloe's friends Blair and Tiff are taking advantage of her, Max and Phoebe receive a mission from Super President Kickbutt to go undercover in Secret Shores. They bring Chloe along with them so she can make real friends and live a normal life. Dr. Colosso also goes along for the ride after a mysterious figure who recently contacted him back in The Thundermans Return wants him to procure a specific item in exchange for regaining his human form. Upon arrival at the condo in Secret Shores and meeting the virtual assistant Thunderford, Phoebe and Max begin their mission while Chloe is enrolled in Secret Shores School where she befriends Booch and Jinx. Dr. Colosso finds that he has been tricked into getting the key card to the weapons vault enabling the villain Malware to reclaim his sentient Giga Gauntlet. Chloe finds out the truth about why she was brought to Secret Shores and teleports back to Hiddenville as Max and Phoebe are told by Super President Kickbutt that Malware has escaped from prison. Tracking Malware down to his lair, Max and Phoebe fight them where he gets thawed out, subdues them, and tied them to a chair so that they would be burned by his "fire wall". After returning to Hiddenville and learning that Phoebe and Max were right about Blair and Tiff, Chloe returns to rescue Phoebe and Max where they defeat Malware and confiscate his Giga Gauntlet. Upon being told about Malware's arrest and Dr. Colosso being under house arrest, Super President Kickbutt shows Phoebe and Max the encrypted transmission of the villain Mastermind on the Evil Web who inviting villains to come to Secret Shores to join a new incarnation of the Villain League. This causes Max, Phoebe, and Chloe to remain in Secret Shores so that they can thwart any villains that show up.

Special guest stars: Chris Tallman as Hank, Rosa Blasi as Barb, Diego Velazquez as Billy

Guest stars: Ryan Ochoa as Malware, Nikolai Witschl as Mastermind, Mela Piertropalo as Blair, Ivory Baker as Tiff, Daniele Gaither as President Kickbutt

During a superhero training with Phoebe and Max to prepare for confronting Mastermind, Chloe is accidentally hit by a gamma energy ball when it was exposed to Phoebe's sunscreen causing her to turn invisible. Scanning Chloe, Thunderford states that the combination has caused a disruption to Chloe's powers as he works to find a cure. Dr. Colosso can't help out when Thunderford states that he never finished the evil medical degree making him three credits short. Phoebe and Max work to control Chloe only for her to get random superpowers as Thunderford states the mutation is causing her to tap into the different powers of the Thunderman family. Even though it appears that Max had managed to get Chloe's powers fixed with a gamma energy ball with a reversed electro-magnetic field, Thunderford cautions Phoebe and Max that Chloe will experience a new power which will affect her appearance at a party held at Splat By-The-Sea where she shapeshifts into a cupcake. Thanks to a tactic by Phoebe and Max, they were able to find the cupcake that is actually Chloe. As Thunderford tells Phoebe and Max that he found a cure for Chloe's condition and sent the prescription to a local super doctor, Dr. Colosso gives an online speech over his graduation of Evil University Online Course only to find out that he was on mute.

Guest star: Michael Delleva as Wayland

To blend in at Secret Shores, Max gets him and Phoebe jobs at Secret Shores School where Max becomes its vice-principal while Phoebe becomes its art teacher much to Chloe's surprise as Phoebe mentions that she is terrible at art. At Secret Shores School as Max and Phoebe argue, Principal Taylor tells Chloe about the Mascot Masc-Off where whoever comes up with the best design for the mascot will have the mascot become the new mascot for Secret Shores School. They used to have an otter mascot, but they had to change it because the new vice-principal and art teacher were mentioned to have been attacked by a family of otters. Chloe ropes Kombucha and Jinx into participating. Upon learning about the fake information that Max made about her that claimed that Phoebe spent four months in prison for sampling grapes at the supermarket when shown a copy of the resume by Principal Taylor, Phoebe and Max get into a feud where they accidentally break the head of the narwhal mascot causing Chloe to snap at them for their irresponsibility. After Phoebe and Max make up, Dr. Colosso fixes the narwhal head as he is good at art. With the first entry in the Mascot Masc-Off being a sunscreen mascot, Phoebe and Max were able to complete the narwhal mascot impressing Principal Taylor enough to make the narwhal mascot the winning mascot.

Guest stars: Jennifer Spence as Principal Taylor, Berkley Holtrop as Sunscreen Kid

Thunderford tells Phoebe, Max, and Chloe that the Hero League has sent over some gadgets to help them on their mission. Phoebe and Max irresponsibly allow Chloe, Kombucha, and Jinx to watch the horror movie One Night at Buster's and eat candy. As a result, Kombucha became extremely energetic and Jinx became frightened. Because of this, Kombucha's dad Randy and Jinx's mom Adele want to meet Chloe's. However, Hank and Barb were up on a three-day mission at the Hero League's Lunar Space Base with Nora and Billy. Therefore, Max and Phoebe use the Disguise-alizer to transform into them respectively to help Chloe maintain her friendship with Kombucha and Jinx. Things go awry when the real Hank and Barb show up out of suspicion, who subsequently transform into Max and Phoebe after figuring out what happened causing Chloe, Max, and Phoebe to find a way to rectify this before their cover is blown and Chloe loses her friends. When it ends up botched and everyone regains their true forms, Chloe convinces Principal Taylor to talk good about the Thundermans. This works and Randy and Adele allow Kombucha and Jinx to remain friends with Chloe. Once they are gone, Principal Taylor was revealed to be Dr. Colosso in disguise. Hank and Barb confiscate the Disguise-alizer and leave to bring Billy and Nora back from the Moon as Hank flies through the roof as usual.

Special guest stars: Chris Tallman as Hank, Rosa Blasi as Barb

Guest stars: Katrina Reynolds as Adele, Toby Berner as Randy, Jennifer Spence as Principal Taylor

At Splat By-The-Sea, Phoebe, Max, and Chloe dine here as Max has been avoiding his turn to wash the dishes at the condo as they meet up with Kombucha and Jinx. Phoebe meets a surf shop employer named Trey after bumping into some of his surfboards outside Splat-By-The-Sea while checking for any security feed involving Mastermind. Back at the condo, Phoebe shows Max and Chloe the security footage of a suspicious ice cream truck that has been driving around Secret Shores at weird hours. In order to have Phoebe get a normal life, Chloe plans to help her ask out Trey. Max does a bet with Phoebe where he will do the dishes from now on if Phoebe can turn off Thundergirl for an entire day. If Phoebe fails, Chloe will do the dishes from now on. Outside Splat-By-The-Sea, Phoebe works to impress Trey. Back at the condo, Max hasn't been able to detect crime as Dr. Colosso advises Max to win the bet as Max's hands prune up easily. Phoebe comes in stating that she scored a date with Trey. After Phoebe leaves, Dr. Colosso and Max come up with a fake emergency to make Chloe lose her bet. Thunderford helps Phoebe pick out an outfit for her date with Trey. Max attempts to get Phoebe to get her to become Thundergirl to handle supposed emergencies like a sinkhole on Main Street (which Chloe claims Secret Shores doesn't have) and a mutant octopus terrorizing Secret Shores. At Splat By-The-Sea, Booch and Jinx try to find Jinx's other earbud. Recalling that his other earbud fell into the mixer for the dinner rolls, they try to get into the kitchen only for Wayland to mention that the dinner rolls have already been made. As Chloe helps Phoebe make her date go off without a hitch, Max calls claiming that he found the suspicious ice cream truck. Chloe leaves to make sure Max isn't faking an emergency as she advises Phoebe to date Trey. Chloe confronts Max near the ice cream truck assuming that Max is trying ruin their date. Just then, they are ambushed by an ice cream vendor-themed villain named Brain Freeze whose gun induces brain freeze on them enough to make them unable to use their superpowers. With Max and Chloe incapacitated, Brain Freeze plans to unleash his hypno-sonic speakers that will brainwash the people of Secret Shores into following Mastermind. Brain Freeze gets a call from Mastermind on his "cell cone" who is displeased that he is operating an ice cream truck at night and to find out Max and Phoebe's identities. Back at Splat By-The-Sea, Kombucha and Jinx are told by Wayland that they now have to pay for the dinner rolls they damaged as Jinx finds his other earbud in his pocket while losing his other earbud as Wayland drives them out. Because of the voice message by Max with Chloe confirming his story, Phoebe ends up leaving her date with Trey. Because of this, Phoebe had to leave the date and come to Max and Chloe's rescue. She destroys the hypno-sonic speakers, disarms Brain Freeze of his brain freeze gun, and freezes him. Phoebe then mentions that she is getting a surfing lesson from Trey tomorrow. As Max claims that Chloe lost the best, he ends up caving when Phoebe and Chloe start to leave him while partially tied up by stating that he'll do the dishes. Phoebe frees Max and they take their leave.

Guest stars: Nikolai Witschl as Mastermind, Michael Delleva as Wayland, Wei Chung as Trey, Tony Alcantar as Brain Freeze