The kids learn that Dr. Colosso ruined their parents' wedding years earlier, and want to recreate Hank & Barb's dream day as their anniversary gift. However, Dr. Colosso remains a threat, and they must keep their plans a secret.
Preoccupied with Z-Force training, Phoebe & Max learn that they’ve forgotten special family events. Wanting to make it up Phoebe plans a family fun day. But when things go awry, she stops at nothing to make it the best day ever.
Phoebe worries that Max will revert to his evil ways after he is asked to give a "Scared Straight" talk to a group of young supervillains in prison, but her efforts to protect Max from himself end up doing more harm than good.
When Phoebe learns Max's band plans to dump him, she suspects that his superhero training is hurting his friendships. Determined to help, she attempts to repair things with the band, but her good deeds quickly backfire.
Max and Phoebe ask Cherry to secretly fill-in after Phoebe injures herself the night before a meeting with the Z-Force, but a superhero emergency tests their scheme and the twins' future as crimefighters.
The Thundermans travel to Hawaii for summer vacation, but there is trouble in paradise as Phoebe inadvertently has absorbed Dark Mayhem's evil powers, and now is determined to complete his plan for world domination.
Tired of hearing tales of Hiddenville's legendary mayor, the kids use a time machine to travel back 60 years to disprove the myths; but when they inadvertently alter the past, the effect spells disaster for their hometown.
Sparks fly between Phoebe and Cherry's visiting brother, prompting Cherry to grow concerned that she will be overshadowed by this new romance; after Cherry begs Phoebe not to date her brother, Phoebe must decide between love and friendship.
Nana and Pop Pop Thunderman come to visit, but when Phoebe reveals Colosso is living in their house, Pop Pop's no-tolerance attitude toward supervillains leads him to banish Max and his bunny best friend to the Detention Zone.
Max finally declares his independence from his parents' house rules and moves to his friend's house, where they only rule is that there are no rules; ultimate freedom quickly becomes more than Max can handle.
Max and Phoebe advance to the final tryout for a spot on an elite superhero squad, but a new super villain with a surprise connection to the Thunderman family may force them to sacrifice their crime fighting dream.