Animorphs Books in Order

Animorphs is a young-adult science fiction series in which five human kids and one alien gain the power to morph into any animal they touch, using it to wage a secret guerrilla war against the parasitic Yeerk invasion of Earth. The main run spans 54 numbered novels (1996-2001), supplemented by the Megamorphs and Chronicles companion volumes.

Publication order

In the order the books were originally released.

  1. Cover of The Invasion

    The Invasion

    1996 · Katherine Applegate

    Five ordinary kids take a shortcut through an abandoned construction site and witness a dying alien crash-land his ship. Before he perishes, the…

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  2. Cover of The Visitor

    The Visitor

    1996 · Katherine Applegate

    Rachel grows suspicious that the assistant principal at school is a high-ranking Yeerk, and that his daughter may be an innocent caught in the…

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  3. Cover of The Encounter

    The Encounter

    1996 · Katherine Applegate

    Tobias, trapped in the body of a hawk, struggles with his fading humanity while the team uncovers a Yeerk scheme involving a hidden mountain lake. As…

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  4. Cover of The Message

    The Message

    1996 · Katherine Applegate

    Jake and Cassie begin sharing strange dreams that seem to call to them from beneath the ocean. The visions point to a survivor of the Andalite ship,…

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  5. Cover of The Predator

    The Predator

    1996 · Katherine Applegate

    Marco wrestles with whether to keep fighting, especially after learning something that hits painfully close to home. When the group is captured and…

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  6. Cover of The Capture

    The Capture

    1997 · Katherine Applegate

    Jake is taken by force and infested by a Yeerk, giving readers a chilling look at what it feels like to lose control of your own body. As the slug…

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  7. Cover of The Stranger

    The Stranger

    1997 · Katherine Applegate

    Rachel and the others discover a hidden Yeerk operation beneath a shopping mall, and an encounter with a mysterious, godlike being called the…

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  8. Cover of The Alien

    The Alien

    1997 · Katherine Applegate

    Ax, the young Andalite stranded on Earth, takes center stage as he balances loyalty to his own people with his growing bond to his human friends.…

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  9. Cover of The Secret

    The Secret

    1997 · Katherine Applegate

    When the Yeerks threaten a stretch of forest that the team has used as a refuge, Cassie leads the fight to protect the wildlife and a colony of…

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  10. Cover of Animorphs - The Android

    Animorphs - The Android

    1997 · Katherine Applegate

    The team encounters an android named Erek, a member of a peaceful ancient alien race called the Chee who have been hiding on Earth for thousands of…

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  11. Cover of The Forgotten

    The Forgotten

    1997 · Katherine Applegate

    Jake is hurled through time and finds himself in a strange future where the war against the Yeerks has taken an unexpected turn. Struggling to…

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  12. Cover of Animorphs - The Reaction

    Animorphs - The Reaction

    1997 · Katherine Applegate

    Cassie's morphing power begins malfunctioning, causing her to involuntarily transform at the worst possible moments. As the team investigates the…

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  13. Cover of The Change

    The Change

    1997 · Katherine Applegate

    Tobias is given a fateful choice by the Ellimist that could change his nature and his future. As the team learns more about the Yeerks' plans and an…

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  14. Cover of The Unknown

    The Unknown

    1998 · Katherine Applegate

    While investigating a secret Yeerk operation hidden near a desert tourist trap, the team goes undercover among wild horses. Cassie narrates as the…

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  15. Cover of Animorphs - The Escape

    Animorphs - The Escape

    1998 · Katherine Applegate

    Marco accompanies the others on a dangerous underwater mission to a Yeerk facility, where the team morphs sea creatures to infiltrate the enemy's…

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  16. Cover of The Warning

    The Warning

    1998 · Katherine Applegate

    The team discovers that the Yeerks are using the internet to recruit and manipulate humans into joining their cause willingly. Tobias and the others…

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  17. Cover of The Underground

    The Underground

    1998 · Katherine Applegate

    The Animorphs discover that a substance affecting Yeerks could become a powerful weapon, sending them deep into the Yeerk pool beneath the city. Jake…

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  18. Cover of The Decision

    The Decision

    1998 · Katherine Applegate

    Ax and the team are accidentally flung into Zero-space during a mission, leaving them stranded far from Earth. Cut off from home, the Animorphs must…

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  19. Cover of The Departure

    The Departure

    1998 · Katherine Applegate

    Cassie, exhausted by the moral weight of the war, walks away from the team to be alone in the woods. There she meets a young girl with a hidden…

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  20. Cover of The Discovery

    The Discovery

    1998 · Katherine Applegate

    An Andalite device with the power to alter reality falls into human hands and ends up in the possession of a boy who has no idea what he holds. Marco…

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  21. Cover of The Threat

    The Threat

    1998 · Katherine Applegate

    The Yeerks unleash a ruthless new human-Controller named David, and the team faces a fresh recruit of their own whose loyalty is dangerously…

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  22. Cover of The Solution

    The Solution

    1998 · Katherine Applegate

    The conflict over the dangerous new Animorph reaches a breaking point, forcing the team to make a terrible decision. Cassie's compassion clashes with…

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  23. Cover of The Pretender

    The Pretender

    1998 · Katherine Applegate

    Tobias learns startling truths about his own family and origins, including a connection that ties him more deeply to the war than he realized. As the…

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  24. Cover of The Suspicion

    The Suspicion

    1998 · Katherine Applegate

    A second, microscopic alien threat called the Helmacrons arrives on Earth aboard a tiny spaceship, and they shrink the Animorphs down to fight for…

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  25. Cover of The Extreme

    The Extreme

    1999 · Katherine Applegate

    The team discovers a Yeerk base hidden in a frozen wilderness and must endure brutal cold to investigate the enemy's plans. Marco leads a high-stakes…

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  26. Cover of The Attack

    The Attack

    1999 · Katherine Applegate

    The Animorphs are drawn into a conflict involving the Ellimist's ancient enemy, Crayak, and a being known as the Howlers. Whisked away to fight in a…

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  27. Cover of Animorphs - The Exposed

    Animorphs - The Exposed

    1999 · Katherine Applegate

    Tobias and Marco get tangled up with a daredevil television crew while a Yeerk plan threatens disaster beneath the ocean. The team must protect their…

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  28. Cover of The Experiment

    The Experiment

    1999 · Katherine Applegate

    The Yeerks develop a plan involving a fast-food company and a substance that could give them a powerful advantage. Jake and the team go undercover to…

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  29. Cover of The Sickness

    The Sickness

    1999 · Katherine Applegate

    Ax falls gravely ill from an Andalite affliction at the worst possible time, just as a crisis unfolds in the Yeerk pool. Cassie must lead the team…

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  30. Cover of The Reunion

    The Reunion

    1999 · Katherine Applegate

    Marco confronts agonizing personal stakes as the war draws closer to his own family. Forced to choose between the mission and the people he loves, he…

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  31. Cover of The Conspiracy

    The Conspiracy

    1999 · Katherine Applegate

    When a family event threatens to expose the team, Jake faces the danger that the Yeerks may be closing in on his loved ones. The conflict grows…

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  32. Cover of The Separation

    The Separation

    1999 · Katherine Applegate

    A bizarre accident in the ocean splits Rachel into two separate people, each embodying a different side of her personality. As her reckless half and…

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  33. Cover of The Illusion

    The Illusion

    1999 · Katherine Applegate

    Tobias is captured and subjected to brutal interrogation by the team's enemies, who try to break him and learn the Animorphs' secrets. As he endures,…

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  34. Cover of The Prophecy

    The Prophecy

    1999 · Katherine Applegate

    Cassie becomes entangled with the Hork-Bajir and a prophecy tied to their people's struggle against the Yeerks. When an Andalite presence stirs old…

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  35. Cover of The Proposal

    The Proposal

    1999 · Katherine Applegate

    Marco's secret life nearly unravels when his father plans to remarry and move away, threatening the cover that keeps the Animorphs hidden. Meanwhile…

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  36. Cover of The Mutation

    The Mutation

    1999 · Katherine Applegate

    Jake and the team venture deep beneath the ocean and encounter a strange undersea world tied to the Yeerks' expanding ambitions. The mission reveals…

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  37. Cover of The Weakness

    The Weakness

    2000 · Katherine Applegate

    With Jake sidelined, Rachel takes command of the team, but her aggressive instincts are tested when the Yeerks exploit a moment of weakness in the…

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  38. Cover of The Arrival

    The Arrival

    2000 · Katherine Applegate

    A group of Andalites arrives on Earth, but their methods and intentions raise unsettling questions for Ax and the team. As the newcomers pursue their…

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  39. Cover of The Hidden

    The Hidden

    2000 · Katherine Applegate

    During a mission, Rachel acquires a unique animal and the team becomes entangled with a Hork-Bajir while evading the Yeerks in the wilderness. The…

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  40. Cover of The Other

    The Other

    2000 · Katherine Applegate

    Ax and Tobias encounter two other Andalites living secretly on Earth, raising new questions about who can be trusted. As the team investigates, they…

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  41. Cover of The Familiar

    The Familiar

    2000 · Katherine Applegate

    Jake is thrown into a disturbing future where the Yeerks have conquered Earth and humanity has been enslaved. Trapped in this nightmarish world and…

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  42. The Journey

    2000 · Katherine Applegate

    The Helmacrons return, once again shrinking down to wreak havoc as they pursue their own bizarre goals. Marco and the team must deal with the…

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  43. Cover of The Test

    The Test

    2000 · Katherine Applegate

    Tobias is lured into a confrontation tied to the dangerous human-Controller Taylor, who manipulates him into a plan against the Yeerks. As the scheme…

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  44. Cover of The Unexpected

    The Unexpected

    2000 · Katherine Applegate

    Marco finds himself stranded far from home and caught up in an unexpected adventure involving an alien threat the team didn't see coming. With his…

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  45. Cover of The Revelation

    The Revelation

    2000 · Katherine Applegate

    Ax takes the lead as long-held secrets about the Andalites and the war come to light, shaking his faith in his own people. The revelations force the…

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  46. Cover of The Deception

    The Deception

    2000 · Katherine Applegate

    Ax uncovers a Yeerk plot involving a human military vessel that could tip the balance of the war. Infiltrating the operation, he must navigate human…

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  47. Cover of The Resistance

    The Resistance

    2000 · Katherine Applegate

    The free Hork-Bajir colony in the mountains comes under threat, and the team must defend their hidden allies from discovery. Jake leads the effort to…

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  48. Cover of The Return

    The Return

    2000 · Katherine Applegate

    Tobias confronts painful matters of family and identity as the war's pressures mount, including encounters with figures from his past. The personal…

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  49. Cover of The Diversion

    The Diversion

    2001 · Katherine Applegate

    With the Yeerks closing in on the team's identities, the Animorphs scramble to protect their families from being targeted. Jake must orchestrate a…

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  50. Cover of Animorphs - The Absolute

    Animorphs - The Absolute

    2001 · Katherine Applegate

    As the war escalates toward its climax, the team faces growing exposure and a powerful new development in the conflict. The Animorphs must adapt…

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  51. Cover of The Sacrifice

    The Sacrifice

    2001 · Katherine Applegate

    Marco confronts a grim mission requiring a hard sacrifice, while the team weighs how far they will go to win the war. Difficult choices test the…

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  52. Cover of The Answer

    The Answer

    2001 · Katherine Applegate

    With the war nearing its end, the team prepares to take the fight directly to the heart of the Yeerk operation. Jake must make impossible decisions…

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  53. Cover of The Beginning

    The Beginning

    2001 · Katherine Applegate

    In the series finale, the long war against the Yeerks reaches its decisive battle and its aftermath. The Animorphs face the ultimate cost of…

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Companion & related books

Short-story collections and companion titles in this series.

Frequently asked questions

What order should I read the Animorphs books in?

Publication order — Widely recommended by readers and matching Scholastic's numbered 1-54 release sequence Start with “The Invasion.”

How many books are in the Animorphs series?

We list 53 books by Katherine Applegate , published between 1996–2001.

Where can I buy the Animorphs books?

Each title above links to Amazon. As an Amazon Associate we earn from qualifying purchases, at no extra cost to you.

Reading order compiled from author/publisher guidance and verified bibliographic data. Spotted an error? We continuously correct the catalog.