Almost nothing could be as bad as finding out your mother is Visser One, the most powerful leader of the Yeerk invasion of Earth. But it happened to Marco. And even though he's been handling it pretty well, he knew there'd come a time when he'd have to face her again, knowing that the Yeerk in her brain has taken his mother away.So when Marco and the other Animorphs discover that Visser One is overseeing a secret underwater project, they know they have to check it out. But Marco's not sure if this is a battle he'll be able to fight.

Special Agent Puller's brother is the country's most wanted criminal, but his conviction points to a cover-up--and a dangerous enemy bent on burying the truth in this #1 New York Times bestselling thriller. It's a prison unlike any other. Military discipline rules. Its security systems are unmatched. None of its prisoners dream of escaping. They know it's impossible...until now. John Puller's older brother, Robert, was convicted of treason. His inexplicable escape from prison makes him the most wanted criminal in the country. Some in the government believe that John Puller represents their best chance at capturing Robert alive, and so Puller must bring in his brother to face justice. But Puller quickly discovers that his brother is pursued by others who don't want him to survive. Puller is in turn pushed into an uneasy, fraught partnership with another agent, who may have an agenda of her own. They dig more deeply into the case together, and Puller finds that not only are her allegiances unclear, but there are troubling details about his brother's conviction...and someone out there doesn't want the truth to ever come to light. As the nationwide manhunt for Robert grows more urgent, Puller's masterful skills as an investigator and strengths as a fighter may not be enough to save his brother--or himself.

When Marco and the other Animorphs investigate Visser One's secret underwater project, Marco finds out that his mother is his worst enemy -- the leader of the Yeerk invasion of Earth.

When fourteen-year-old Alex is framed for murder, he becomes an inmate in the Furnace Penitentiary, where brutal inmates and sadistic guards reign, boys who disappear in the middle of the night sometimes return weirdly altered, and escape might just be possible.