In a desperate attempt to escape another "lesson" (bullying session) from Jake "the Snake," Mouse and his friends Shelby and Lucy take shelter in the old, supposedly haunted, Holsom barn. When one of Jake's friends, Jorge, discovers them hiding in the barn's silo, a scuffle breaks out and a hidden button is accidentally pressed. Suddenly the silo floor descends like an elevator!
Once the elevator stops, our gang makes their first discovery: Horatio Holsom, the eccentric old inventor who disappeared over forty years before, built an enormous underground laboratory below his family's farm. The place is packed with incredible gadgets, but only Mouse—a near genius with computers—is interested in staying. The elevator seems broken, and Jorge is still intent on roughing up Mouse. Their arguments are interrupted by a cold, metallic voice. The four kids learn they are not alone in the compound.
Jorge lies, telling the robot that he and the others were sent to the compound by Horatio Holsom. The robot, now nicknamed "Rover" by Mouse, fixes the broken elevator that brought the kids to the laboratory and allows them to go home.
Afterward, Lucy's parents ground her for staying out so late and for not telling them where she had really been. She confides to her brother Noah who promises not to tell anyone if Lucy will tell him the truth. But Noah has a hard time believing the tale involving a secret underground laboratory and a giant robot.
Jake continues to terrorize Mouse. Jorge steps in and helps Mouse out of a jam—but what's his real motivation? Jordan gets into trouble for talking too much at church, and one of Holsom's more unusual residents makes a surprising trip to town one Sunday afternoon. It seems Otto Farless is preparing for some kind of hunt. But when it comes to Otto, who claims to have seen mechanical aliens near the old Holsom barn when he was a kid, anything is possible...
Meanwhile, Jorge forces Shelby and Mouse to let him in on their little secret. And Mouse gives Rover an "upgrade" with surprising results.
Being popular is very important to Jordan, and she'll go to extreme lengths to stay that way! Jordan caves in to peer pressure and lies to her parents so she can attend a less-than-wholesome party.
Meanwhile, Mouse gets a lesson in intelligent design from an unexpected source. Then, in spite of Noah's rescue attempt, Jordan's father catches her trying to sneak back into her room. But Jordan seems more angry than apologetic...
J.D. Raye, a powerful businessman, has a mysterious interest in Holsom and has sent an agent, Constance Vile, to investigate the little town. J.D. and Constance seem to be scheming to take the farm away from Shelby and her dad. But why?
Plus, you're invited to dinner! Join Shelby, Mouse, Jorge—even (gasp!) Jake "the Snake" for a sneak peek into each family's life that should provide plenty of "food for thought."
Noah's best friend, Jordan, struggles with negative peer pressure. As an ominous storm approaches, Jordan deceives her parents and joins some friends on a so-called "double date" with an older boy.
Meanwhile, Jorge and Shelby "accidentally" invite Otto Farless to church, and Mouse and Jake have a fateful encounter that will have severe consequences for everyone.
Jordan finds herself in deep water—literally! As the raging storm pounds the countryside, Jordan's life is suddenly in peril.
As the good people of Holsom try to survive a storm-tossed evening, sightings of a strange, 12-foot tall creature are reported.
When Rover returns to the compound, Mouse—furious at Jake for destroying his treasured laptop computer—instructs the robot to go to Jake's house to teach the bully "a lesson."
After Jordan's life-changing experience, will Noah finally believe Lucy's "robot "story? Also, as a fierce storm continues to pound the little town of Holsom, Rover carries out Mouse's plan for revenge, accidentally revealing his existence to several people.
Meanwhile, on an archeological dig in New Mexico, JD Wray discovers the head of an unknown robot that looks a lot like Rover...
Otto remembers the first time he encountered Rover, and JD promises to rebuild the town of Holsom. Meanwhile, Noah gets his first tour of Horatio's underground compound, where Mouse has to answer for his recent disastrous instructions to Rover.
JD obtains photos taken of Rover and begins to add members to his little robot-hunting squad, beginning with Jake "the Snake..."
Constance and Jake corner Jorge and convince him to tell them all about Rover. Together with JD, they pay a surprise visit to Mouse, who is home alone. But this unexpected and unwelcome visit is not nearly as shocking as the strange visitor who shows up at the local church...
After cornering Jorge and convincing him to tell them all about Rover, Constance, Jake, Jorge, and JD grab Mouse and go to the underground laboratory. They are unaware that Lucy is already hiding there or that Shelby's dad is racing toward the old barn, hoping to discover the truth for himself. Suddenly, Lucy turns out the lights, and Jorge and Mouse make a narrow escape by using Rover to blast through the roof!
JD Raye gets his wish when he finally stands face-to-face with Rover.
When the smoke clears, JD, Jake, and Constance have narrowly escaped the explosion. JD wastes no time covering his tracks. Can even silver-tongued JD explain his way out of this one?
Also, just how far can Rover actually fly? And what happened to Lucy when the ceiling collapsed?
Ralph and Ruben close in on their prey. While running for their lives, Mouse and Jorge discover something in the deep woods that might be scarier than anything they've faced before—a mysterious girl who may not be everything she seems. Find out if even Rover can be frightened!
While the town searches above ground, 50 feet below Lucy runs for her life from two decidedly unfriendly robots. Lucy escapes and unintentionally reveals to JD Raye that she was chased by two other robots.
Meanwhile, Jorge, Mouse, and Rover travel farther from Holsom, unaware they're being hunted...
What's worse than being alone? Lucy finds herself trapped in the massive cave system beneath the old barn. Unfortunately for her, she is not alone. Or what's worse than being tracked down by Constance Vile? You will find out! Everyone's hunting for the answers, but no one's going to like what they find.
Plus, Tabby and Jordan have a conversation that begins to change their relationship.
The sheriff of Holsom spends a late night reviewing all the evidence: Does he believe a giant robot ran off with Mouse and Jorge? Plus, we get a revealing glimpse at Horatio's journal, Constance's notes, and Lucy's diary.
All the while, Ralp and Ruben are hot on the trail of our runaways.
Jorge, Mouse, and Rover travel farther from Holsom, unaware they're being chased by two local hunters, Ruben and Ralph, as well as Sheriff Owens, who finally believes all the crazy robot stories he's been hearing.
Meanwhile, Lucy deals with evil-robot nightmares, while Jordan stands up for Tabitha during an ugly game of dodgeball. JD looks for more robots, and Mouse and Jorge get an unexpected surprise.
The warrior robots head toward downtown Holsom, where a parade celebrating the first JD Raye Day Festival is underway. Rover and company hitch a ride aboard a train, hoping to reach Holsom before Horatio's other robots tear the town to pieces. Meanwhile, Jordan, Noah, Shelby, Tabby, and Lucy try to avoid getting smashed by flying debris..
This is it! Is this Rover's last stand? Will Lucy's nightmares come true? Who will end up with Horatio's journal? Will Otto save the day or ruin it? The astonishing ending involves ultimate sacrifice, betrayal, and true friendship. The town and everyone in Holsom will never be the same.