Douglas creates a device that makes any bionic human as smart as Chase. After Douglas tests it on Bob, Bob starts spending time with Chase. This leaves Adam in envy. Meanwhile, Perry made the island officially her own, which makes Bree and Leo angry at her.

Adam, Bree, and Chase are looking for Leo because he is late for training and find out he is in Mission Creek because Janelle threatened to break up with him. S-1 shows up unexpectedly and shocks everyone. She came to the island because, like everyone else, her memory is blank, but has continuing flashbacks of Krane.

Douglas tells the group that his old college ex-girlfriend, a film director named Giselle, will be making a film titled Bionic Action Hero based on all of them and starring an up-and-coming actor named Troy West. Giselle and Troy visit the island to learn about the bionic team.

Douglas tells the group that his old college ex-girlfriend, a film director named Giselle, will be making a film titled Bionic Action Hero based on all of them and starring an up-and-coming actor named Troy West. Giselle and Troy visit the island to learn about the bionic team.

Donald's top scientist, Dr. Ryan, arrives to test Chase's invention. The two of them dislike each other and don't get along. When Donald puts Dr. Ryan in charge of the space elevator, Chase immediately gets jealous. Donald then makes Chase Dr. Ryan's assistant. Dr. Ryan puts Chase in charge of screwing in the lug nuts, but Chase refuses, and Dr. Ryan builds the space elevator without Chase. The day of the launch, Chase performs a bionic scan of the elevator and finds a major braking flaw on the elevator.

Chase and Donald have invented a new technology that takes in energy from any environment. Chase feels that he does not get his share of spotlight when Donald sells the product without his approval. Meanwhile, Kaz comes to the bionic academy to get powers, bringing Oliver with him.

Douglas finds out that there is a student named Kate with the Commando App. Chase tries to activate her Commando App, named Spikette by Douglas, so he can research her. When he starts fighting with Adam, she activates her Commando App and thinks Chase is her baby. While she destroys the bionic academy, Bree forces Chase to activate his Commando App by embarrassing him so he and Kate can battle. Unfortunately, he teams up with her. Douglas gives Bree a Commando App and she and Kate begin battling each other. Bree wins and Douglas extracts Kate's chip. Chase apologizes to Kate and finds out that Douglas replaced her Commando App with sonic screaming.

Chase and Douglas reanimate a prehistoric sea spider. It escapes and bites Adam, which poisons him. It then grows and becomes 50 feet long due to growth hormones that had been given to it by Douglas. Everyone tries to stop the spider so they can create a cure for Adam.

When Leo is injured during a mission, Tasha rushes to the academy to take care of him. After finding out what happens on missions, she bans Leo from joining any more missions, but he disobeys her and goes on a mission with the rest of the team. When Tasha finds out, she kicks Leo off the team and tells him that he is moving back to Mission Creek.

Adam and Chase each lead their own student groups against each other in a series of simulated exercises that will evaluate both student and mentor performance. However, after Chase's group fails at defeating the exoskeleton and defusing a virtual bomb, Chase decides to find a way to cheat and win.

The Lab Rats are on a mission to save people from a wildfire; when the people start to chant Adam, Bree, and Chase's names, Leo gets jealous and wants to become known. Douglas gets put in charge to develop a new technology for the academy, but can only come up with things that can hurt the students.

Adam brings a dog back to the island and Douglas reveals that it's his old dog, Otis, who Douglas made bionic in order to save his life when Otis was injured. Chase turns out to be allergic to dogs as he starts sneezing, so Douglas says that Otis has to leave, but he and Adam actually hide the dog. Meanwhile, Leo gets a new smartphone application assistant named Shelly, with whom he has fallen in love.

When suspicious events happen overnight on the bionic island, everyone is convinced a new threat has emerged. However, this threat is revealed to be Leo, when his bionics glitch because Douglas never gave Leo a capsule.

After sneaking some students off the island and to the mainland, the Lab Rats accidentally leave Spin and Bob behind and must retrieve them before Donald finds out. Meanwhile, Donald tries on Chase's mission suit and he and Leo scramble to get it off before Chase gets home.

Sebastian has secretly formed an evil rebellion to get revenge on the Lab Rats for destroying his father. Meanwhile, Leo is trapped with the other bionic people who also want revenge, but Leo manages to convince Spin and Bob to help him, and, in the end, Sebastian is defeated, his rebellion is brought down, and he and his comrades are taken to a facility. Meanwhile, Donald successfully convinces the others that he has the best interest for them at heart while Adam still blames Chase for everything that happened after the rebellion is over.

Sebastian has secretly formed an evil rebellion to get revenge on the Lab Rats for destroying his father. Meanwhile, Leo is trapped with the other bionic people who also want revenge, but Leo manages to convince Spin and Bob to help him, and, in the end, Sebastian is defeated, his rebellion is brought down, and he and his comrades are taken to a facility. Meanwhile, Donald successfully convinces the others that he has the best interest for them at heart while Adam still blames Chase for everything that happened after the rebellion is over.