The Anders family hosts Casey, a spy, for dinner, hoping to learn more about her and Whittier. Tensions rise as they try to decipher her motives and background. The dinner takes a dangerous turn when Whittier attempts to contact Casey, revealing her location and forcing the family to contemplate an escape.
Holiday and Casey's confrontation in the girls' bathroom reveals Casey's mission to find the "four" for Whittier. Casey explains her methods and motives, while also trying to protect Cyrus. Amidst the tension, Casey receives a dinner invitation from Holiday's parents, and Brinley begins investigating Casey and Whittier.
Holiday and Birdie track Cyrus to a mysterious field, where they encounter a trap and confront him about his actions. Cyrus reveals his plan to infiltrate Whittier Labs using his science fair prize to bring the corporation down. Back at school, Holiday faces Casey, foreshadowing a potential confrontation.
After discovering Casey's betrayal, Cyrus is heartbroken, leading to a tense family discussion about trust and safety. Cyrus attempts to leave, but is stopped by his parents. Ultimately, they decide to invite Casey over for dinner to gauge her trustworthiness, while Casey secretly heads to Whittier Labs, setting the stage for further conflict and uncertainty.
The Anders family grapples with the fallout of Casey's betrayal as they try to understand her motives. Casey attempts to gain Cyrus's trust by revealing her own background and offering to help them against Whittier. The family must decide whether to trust Casey's offer of assistance while protecting themselves from Whittier.
Following Flashcard's reveal, Cyrus confronts Casey, who is exposed as the spy working for Whittier. The Anders family must escape as Whittier closes in. Cyrus grapples with Casey's betrayal and the family's uncertain future while seeking safety.
Birdie and Cyrus search for Holiday and the missing hoverboard, uncovering secrets and confronting Brinley. Holiday demands answers from Flashcard regarding their motives, leading to surprising revelations. Ultimately, Cyrus discovers the identity of Flashcard in the gym.
Holiday and Brinley are trapped, leading to a confrontation about their true identities and Brinley's motivations. Meanwhile, Cyrus and Birdie search for Holiday, discovering that others have also disappeared. The episode builds tension as the Childcatchers close in, and the kids must rely on their hoverboard for help.
Holiday and Cyrus prepare to trap Flashcard at Holiday's middle school jazz concert, while Bertie is tasked with watching for suspicious behavior and uses a walkie-talkie app to communicate with Cyrus. Holiday and Brindley find themselves locked in a supply closet.
Holiday and Cyrus free Hovey from the garage, only to have him fly up to a power line. Holiday apologizes for locking Hovey up and convinces him to come back so they can proceed with their plan to trap the Whittier spy at the concert. They discuss the plan with family and friends, solidifying their strategy.
The Anders family discusses the Whittier helicopter sighting and whether it was a trap set by Flashcard to identify Holiday. Birdie feels responsible, but the family tries to figure out who Flashcard is and how to protect Holiday. Holiday decides to use herself as bait to draw out Flashcard and seeks help from an unexpected source.
In this episode, the kids notice low-flying helicopters and Birdie's strange reaction, leading to her pulling the fire alarm. The group discusses the upcoming concert and the creepy encounters that are surrounding it. Holiday comes up with a risky plan of her own to deceive Whittier and their spy.
Cyrus and Casey work on their robot project, Hermione, facing both technical challenges and emotional revelations. After a mishap during the robot's activation, Casey reveals her high hopes for the project, while Cyrus shares his admiration. An emergency announcement interrupts their conversation, hinting at future problems.
Holiday and Cyrus discover someone snooping around their garage, leading to a confrontation with Brinley. Brinley is suspected of being a spy and unleashes a squirrel. Amidst the chaos, Birdie pressures Cyrus about an upcoming concert, but the family plans to use the concert to expose Flashcard.
Brinley confronts Simon and Casey about their break-in, using Hermione to expose their lies. Holiday and Cyrus suspect Brinley is a spy, leading them to believe they are not safe. The episode intensifies as the siblings discover someone is in their garage, creating suspense about the hoverboard.
Holiday and Cyrus are caught breaking into Brynleigh's house, but a quick-thinking classmate named Tiffany helps them escape. Suspicious of Brynleigh's seemingly normal life, they question her true identity and motivations. Cyrus and Holiday navigate their changing relationship amidst the spy mystery.
Holiday and Cyrus sneak into Brinley’s cabin to retrieve Holiday's stolen phone, joined unexpectedly by Casey. After navigating the remote location and Brinley's heavily taxidermied house, they locate the phone just as Brinley's dad returns, increasing the tension and risk of getting caught.
Holiday suspects there is a student spy working for Whittier Corporation, and that student might be Brinley. During volleyball practice, Brinley ends up with a broken nose, and Holiday and Casey end up with a suspension. Holiday's phone is stolen with all her voice memos, leading her to believe that Brinley is Flashcard, so Holiday plans to break into Brinley's house to get her phone back.
A reporter interviews the Anders family about Cyrus's robotics competition, but Holiday suspects the reporter is digging for more information about the family's secrets. The family tries to deflect questions about a 'spy' at school, leading Holiday to suspect a classmate named Brinley.
Birdie's strange behavior at school raises concerns, leading Holiday to confront her about a secret. A visit to the school nurse reveals potential issues, and a mysterious jacket with a coded message surfaces, hinting at a spy within the school. The sisters must decipher the clue to uncover the truth.
Holiday suddenly speaks fluent French due to Cyrus's experiment, leading to a discussion about her abilities. Cyrus has entered a science fair with Casey, which requires a newspaper interview. The family grapples with the risks of attracting attention, but Holiday insists Cyrus should proceed, leading to a compromise where she avoids the interview.
Holiday's newfound musical talents cause conflict with Brinley, leading to suspicion and rivalry. Cyrus attempts to understand Holiday's abilities, suspecting they are superpowers related to the Whittier Corporation. Holiday tries to downplay her gifts and seeks normalcy, but the mystery deepens when her powers suddenly disappear, prompting Cyrus to investigate further.
Cyrus's attempt to be normal is disrupted when Principal Palais reveals he and Casey have been chosen to represent the school at the Alaskan STEM competition. Concerns about family attention arise, but the potential for a Whittier Corporation scholarship sways Cyrus. He agrees to participate, setting the stage for an unusual partnership with Casey.
Holiday and Cyrus try to return to normal school life, but Holiday's attempt to apologize to Brinley fails. During music class, Holiday unexpectedly demonstrates talent on the oboe, leading to accusations of a setup by Brinley and a declaration of war. Holiday's special abilities continue to surface, making normalcy difficult.
Holiday rescues Birdie from a tower using her hoverboard. The family discusses the dangers they are facing and considers moving. Holiday decides to stop searching for answers about her past to protect her family, unaware that Badger is being interrogated and that there is a spy in her school.
The team investigates a creepy warehouse in search of Badger, where they discover a disturbing interrogation room with child-sized handcuffs. Birdie spots someone atop a radio tower and decides to climb it, despite her fear of heights, believing it to be Badger.
Holiday's family is determined to find Badger and uncover the truth about Holiday's past. Holiday uses her connections to track the van that took Badger, leading them to a creepy warehouse. The family arrives at the warehouse and prepares to search for Badger, despite the potential dangers.
The Anders family grapples with Holiday's disappearance, facing suspicion from the new school principal who threatens to involve Child Protective Services. Cyrus deals with school bullies, while Holiday, who was actually hiding in the attic, overhears her parents' support and offers a deal: she will behave at school if they help her find Badger, someone who knew her before her memory loss.
Holiday has run away after discovering the truth about her past, leaving her family desperate to find her. Cyrus reveals he knew about Holiday's plan and feels responsible. The family unites to bring her back before the Whittier Corporation finds her. Bertie expresses her fear that Holiday may not return, questioning if their family bond is strong enough.
Holiday confronts her parents about their lies and the truth about her origins as a possible lab experiment. Si offers his unwavering support, leaving Holiday to grapple with a difficult decision: stay with the only family she's ever known or venture out alone to uncover her past.
