When ex-Principal Perry moves into Mission Command, she causes Chase to miss a mission. When Skylar fills in as leader, she's successful, making an envious Chase turn the tables, causing Skylar to miss out on the next one. But she and Perry show up after all, leading to a dangerous situation when the three become trapped, leaving Bree, Kaz, and Oliver to think of a way to save them.moreless
Fiona's bad judgments about Robbie catch up with her. Frank and Sammi make up for missed father-daughter time and Army investigators pay Lip a surprise visit at college.
Principal Perry is in danger and the Lab Rats are at risk of exposing their powers to her and Davenport's business is ruined.
Frank comes back to his family, causing trouble along the way. Lip is in college, while Ian is missing and Fiona is doing her best connect with Debbie and Carl.
Principal Perry recruits Leo and Chase to help Trent study for an important test, but they use the opportunity to sabotage him. Meanwhile, Bree tries an experimental cream that causes her hair to grow out of control on school picture day.moreless
When Dr. Evans becomes entrapped in Davenport's secret facility, the team sets out to rescue him for the holidays.
Chase accidentally shrinks Adam when adjusting his strength levels and Bree becomes principal for a day.
The school is woefully behind the times and Davenport upgrades the tech including creating a mechanical Principal Perry which goes haywire after Chase adjusts it's settings.
When Leo's rival claims there's a ghost at the school, he and Chase decide to prank him until they discover it may be true.
When the school mascot costume is stolen by a rival school, Adam kidnaps their llama. Meanwhile Bree and Leo compete against Principal Perry and Caitlyn in dominos.
Adam is tired of not having time off from training, so Eddie convinces him and Leo to make a clone of Adam. Things go awry when the clones self duplicate.
When ultra-super rich Perry Hamilton and son Clayton move into the neighborhood, they make the Davenport family miserable just because they're rich. Perry challenges Donald to a stock car race for the deeds to their houses.moreless
When Adam gets a monster truck, Mr. Davenport doesn't think it is a good idea until he drives it. Unfortunately, he crashes it into the school and now Principal Perry has it.
When a priceless piece of art is missing, the rats must search everywhere to locate it.
Leo and Chase perform magic for the talent show while Bree watches Adam and her boyfriend, Owen, create butter art.
Chase finally succeeds in pranking Adam, causing Adam to get hurt and lose his self confidence.
Fiona starts a new job at an office. Mandy affects Lip's future, while Karen pushes Mandy to the edge. Frank manages to become the public face of a gay rights movement.
When the team is trapped in detention, Leo fills in to help Eddie and Davenport stop a toxic gas leak.
Leo accidentally releases robot flies.
When the rats crave each others bionic abilities, they switch their chips despite warnings from Davenport. When they accidentally trap Leo in an elevator with the principal, they need to learn how to use each others abilities.moreless
Davenport is afraid of letting Chase go to school since his commando app could glitch and activate. The kids must play the football players when they embarrass them.
After Leo and his mom move into his step dad's house, he accidentally finds a secret lab in the basement with three bionic teenagers.