Cassie and her Animorph companions meet a treacherous new enemy, the Helmacrons, tiny but unexpectedly lethal invaders who have the ability to shrink others to their size and who are taking hostages to recover their spaceship.
- ISBN10 0590762575
- ISBN13 9780590762571
- Publish Date 1 December 1998
- Publish Status Out of Stock
- Out of Print 18 October 2010
- Publish Country US
- Imprint Scholastic US
- Format Hardcover
- Pages 155
- Language English