When the Eagles and Ravens start getting too friendly, the headmaster sends them on a grueling two-day hike devised to reignite their competitive fire

The fallout from the hike reverberates inside and outside the school, leading to hard questions -- and a difficult decision.

Brooke scrambles to keep a secret from Alex during an upheaval at the Greenhouse. Sophie's past choices threaten her current status at the school.

As a sinister plot targeting the school unfolds, Hayley embraces her new lifestyle, annoying Leo, while Brooke argues with Alex about her brother.

A remarkable gift from Ryan boosts the Ravens' flagging spirits. Becca smothers Leo with attention. Brooke makes an impulsive, ill-timed decision.

Members of the Eagles and Ravens team up on a risky mission to find a valuable chunk of magnetite. A disheartened Brooke looks to make a fresh start.

While the Eagles and Ravens compete in a capture-the-flag challenge, Enzo receives a mysterious offer that's too lucrative for him to question.

Hayley's determination to get to the bottom of an annoying beeping noise unwittingly sets a deadly chain of events into motion.

Flashbacks reveal a discovery that teenage Ryan made at the Greenhouse and an order given shortly before the Athena launch. Brooke is led into a trap.

During a quiz game, know-it-all Aspen grates on Hayley's nerves and Brooke suffers a strange lapse in memory. Max misses Emma and tries calling her.

When Aspen's jealousy gets the better of her, Leo tells her they need to talk. Judy and Marcus trigger a test quake and get unexpected results.

Under the sea, Hayley experiences something that changes how she thinks about her mom. Believing the world is ending, Parker blurts out a confession.

Sophie finds herself shunned by all the Eagles -- except for one. Daniel gets a hunch as to who might be influencing Brooke's recent behavior.

After catching his mom in lie, Daniel compares notes with Hayley. Aspen makes a slip that shocks Leo. Jackie is tricked into confessing a past misdeed.

Hayley and Daniel attempt to dehypnotize Brooke. Max and Jackie start to see a common thread behind all the strange events surrounding Emma.

Brooke tells Daniel and Hayley the last things she can remember before being hypnotized. Marcus makes a decision that stuns Louis and infuriates Judy.

Leo awakens in the cave. During dinner with their parents, Brooke and Daniel carry out a plan to get Emma's white knight chess pieces from Jason.

When Hayley tells her brother and friends the big news, they argue over whether to take action. Max and Jackie are caught trying to contact Emma.

While Daniel and Alex stall for time at the basketball game, Hayley sneaks into the cave and Max gets help from an unexpected ally.

As time runs out on a bomb designed to destroy the cave and the rest of the Greenhouse, the students in the gym must get past police to make a rescue.

Eight months after the sudden loss of his astronaut mom, Alex undergoes rigorous entrance testing to attend the same leadership high school she did.

For their first challenge, the Eagles and Ravens compete to solve a riddle. To be accepted by his team, Alex distances himself from his older sister.

The Eagles pressure Alex to help them get revenge against the Ravens. FBI agents look for a weapon lost near campus and suspect a student took it.

Brooke spots boyfriend Daniel doing something suspicious on the beach. Jackie gets to know Max's sweet side when he helps her with an assignment.

The secret Daniel has been hiding is dramatically unveiled. Chess whiz Max meets his match. Hayley and Leo's friendship takes a sudden turn.

Hayley gets upset when Leo avoids talking about what happened between them. Max tries to impress his crush, Emma, in gym class.

The Eagles' two candidates for team captain face off in a debate. In class, the students argue over a hypothetical moral dilemma.

Jackie coaches Max in asking Emma out on a date. Jason receives an important but risky mission he must carry out at the satellite launch.

Brooke's investigations lead her to danger and a discovery. When Sophie makes the Eagle boys clean their stinky locker room, a secret is uncovered.

At the school's Harvest Fair, the Eagles and the Ravens compete to see which team can raise more scholarship money by marketing and selling cupcakes.

Ryan's letter reveals a secret she kept from her husband for years. When Emma turns him down, Max takes Jackie instead to the Halloween dance.

Hayley learns who Leo's surprise visitor is. Emma faces consequences for her phone call to NASA. Jealous Daniel's temper explodes at the school dance.