The prophecy [eBook - NC Kids Digital Library] : Animorphs series, book 34

There Is A Chance For The Free Hork-bajir On Earth To Start Their Own Rebellion Against The Yeerks. They Have The Numbers, But They Don't Have The Weapons. They've Learned From The Last Surviving Arn -- The Race That Created The Hork-bajir -- That Aldrea, Daughter Of Prince Seerow, Knew The Location Of A Stolen Yeerk Vessel. Unfortunately, The Only Way To Recover The Ship Is To Ask Aldrea Herself -- And She's Dead. The Arn Have Aldrea's Persona Stored, But To Bring Her Back, They Need A Host Body, And Cassie, Rachel, Or Toby Hamee Are The Closest Matches. The Only Problem Is That Once Aldrea Gets Into One Of Their Minds, She May Not Want To Come Out... Cassie acquires the mind of Aldrea, daughter of Seerow, Andalite Prince, as well as her memory, persona, secrets, and an abundance of valuable information that will help the Animorphs In an effort to help start a rebellion against the Yeerks on the Hork-Bajir home world, Cassie agrees to become the host for the persona of a dead alien.