The Unknown is the fourteenth book in the Animorphs

Animorphs

Animorphs is an English language science fiction series of young adult books written by K. A. Applegate and published by Scholastic. Five humans, Jake, Marco, Cassie, Rachel, and Tobias, and one alien, Aximili-Esgarrouth-Isthill , obtain the ability to morph into any animal they touch. They name...

series, written by K.A. Applegate. It is narrated by Cassie

Cassie (Animorphs)

Cassie is a fictional character from the sci-fi book series Animorphs, written by K. A. Applegate. Her last name is never mentioned, although she referred to it as being "nice" in The Secret.-Biography:...

.The front cover quote is, "Never underestimate the power of a morph....". All books after The Unknown were dedicated to Applegate's son, Jake, as well as her husband and co-writer, Michael. Her son was born premature in 1997, and she worked on the Animorphs series at night, in the lobby of the hospital where he was in Neonatal Intensive Care.
It is assumed that the horse featured on this cover is Minneapolis Max, and not the horse that Cassie acquired as her first morph (which would make this the fifth book to feature a cover morph that was not acquired in the book), despite not fitting Max's description.

Plot summary

Cassie and Rachel drive with the former's father, Walter, to the Dry Lands outside of town. 'Crazy Helen', a client of Walter's, has informed him of a sick horse stumbling about the plains. Helen rants on about Martians while Walter and the girls search for the horse in the dark. Rachel spots it trying to make a call at a pay phone. The horse then tries to escape, but is too weak to walk, and falls over. Cassie and Rachel notice a Yeerk falling out of the dying horse's ear. Cassie, getting a bad feeling, tells Rachel to run. A second later, they're knocked over by an explosion. Cassie wakes up in Crazy Helen's caravan, who insists 'it was the Martians!'. Cassie and Rachel decide she is half right - and assume that the Yeerks were trying to keep them away from the horse.

The other Animorphs are skeptical, though. Rachel and Cassie are frustrated, but Jake allows the group to go back to the site and investigate. Cassie, Rachel, Marco and Tobias travel in bird morph, and land in a rocky outcrop. They're promptly arrested by soldiers, and taken to the Air Force base - Zone Ninety-One. There, they meet Captain Torelli, the chief of base security, who is suspicious of the kid's lack of shoes. Cassie, Rachel and Marco, fearing being grounded, or charged with trespassing, give the captain fake names and phone numbers; Marco calls himself Fox Mulder

Fox Mulder

FBI Special Agent Fox William Mulder is a fictional character and protagonist in the American Fox television shows The X-Files and The Lone Gunmen, two science fiction shows about a government conspiracy to hide or deny the truth of Alien existence. Mulder's peers consider his theories on...

, Rachel Dana Scully

Dana Scully

FBI Special Agent Dana Katherine Scully, M.D. is a fictional character and protagonist on the Fox television series The X-Files , played by Gillian Anderson. She also appeared in two theatrical films based on the series...

, and Cassie Cindy Crawford

Cindy Crawford

Cynthia Ann "Cindy" Crawford is an American model. Known for her trademark mole just above her lip, Crawford has adorned hundreds of magazine covers throughout her career. She was named #3 on VH1's 40 Hottest Hotties of the 90s...

. Marco and Rachel stare at her. Marco gives the number for the sports scores recording, Rachel Pizza Hut

Pizza Hut

Pizza Hut is an American restaurant chain and international franchise that offers different styles of pizza along with side dishes including pasta, buffalo wings, breadsticks, and garlic bread....

, and Cassie replies "one-two-three-four-five-six-seven-eight!" Cassie earns more stares from Marco and Rachel. The captain leaves, and the kids escape via cockroach morph. They escape outside, but Cassie is nearly crushed by a tank. Tobias picks her up, and airlifts the trio to safety.

Cassie decides on a new plan. They need horse morphs from the racetrack. They're nearly caught by the staff, and Cassie morphs Minneapolis Max - a champion stallion. The animal's jockey, assuming Cassie is the real horse, takes her to the starting gate, and she is caught up in a race, which she wins. The Animorphs are now ready to infiltrate Zone Ninety-One.

Back in the Dry Lands, the teens morph their respective horse morphs. They join the alleged Yeerk herd, and trot directly into the base. They hear the horse-Controllers speak Galard - the interstellar lingua franca

Lingua franca

A lingua franca is a language systematically used to make communication possible between people not sharing a mother tongue, in particular when it is a third language, distinct from both mother tongues.-Characteristics:"Lingua franca" is a functionally defined term, independent of the linguistic...

. Ax translates for them, telling them that the Yeerks are planning to complete their mission tonight. The Yeerks promptly break into a run, and rush into a hangar. There, the Animorphs see what the government's been hiding. They know it's not human, but they don't know what it is. Neither do the Yeerks. The Yeerks are depressed and afraid, aware of the consequences for failure. They rendezvous with Visser Three, who decapitates the Yeerk 'responsible' for the failure. The Visser then orders his Hork-Bajir to eliminate the suspicious-looking horses standing close by. Cassie knocks over a Hork-Bajir, and the rest make a break for it. It is then that an embarrassed Ax tells them what the humans have been guarding: a disposable waste module from an Andalite Dome ship; an alien toilet. The disgusted Animorphs decide they've been wasting their time, and head home.

At home, Cassie berates herself for wasting her team's time, but then realizes the significance of the Andalite toilet; it's proof that sentient life exists beyond Earth, and that Visser Three needed humanity to know as little as possible in order for the invasion to continue to run smoothly. Cassie then remembers a pin-up board for 'Gondor Industries'; a dummy corporation employee's day out. ('Gondor Industries' is likely a reference to the third age kingdom of Gondor

Gondor

Gondor is a fictional kingdom in J. R. R. Tolkien's writings, described as the greatest realm of Men in the west of Middle-earth by the end of the Third Age. The third volume of The Lord of the Rings, The Return of the King, is concerned with the events in Gondor during the War of the Ring and with...

 from The Lord of the Rings

The Lord of the Rings

The Lord of the Rings is a high fantasy epic written by English philologist and University of Oxford professor J. R. R. Tolkien. The story began as a sequel to Tolkien's earlier, less complex children's fantasy novel The Hobbit , but eventually developed into a much larger work. It was written in...

: The Return of the King

The Return of the King

The Return of the King is the third and final volume of J. R. R. Tolkien's The Lord of the Rings, following The Fellowship of the Ring and The Two Towers.-Title:...

. Applegate frequently used similar names from the LOTR series in Animorphs series.) Cassie takes the Animorphs to The Gardens amusement park. Cassie figured that Visser Three planned to kidnap captain Torelli and other Air Force staff at Zone Ninety-One. The Animorphs, chased by Captain Torelli, end up in the horror house, where the Hork-Bajir waited. The children morph, and a battle ensues. They wound the Hork-Bajir and rescue the captain from Visser Three. The Yeerks escape in their vessels, in front of totally oblivious humans at a night parade.

Morphs

Morpher	Morphs acquired	Morphs used
Jake Jake Berenson Jake Berenson is a fictional character and one of the main protagonists from the science-fiction book series Animorphs, written by K. A. Applegate. Until the penultimate book of the series, his last name was never revealed, and he was known only as Jake...	Horse Horse The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...	Seagull, Peregrine Falcon Peregrine Falcon The Peregrine Falcon , also known as the Peregrine, and historically as the Duck Hawk in North America, is a widespread bird of prey in the family Falconidae. A large, crow-sized falcon, it has a blue-gray back, barred white underparts, and a black head and "moustache"... , Horse, Great Horned Owl Great Horned Owl The Great Horned Owl, , also known as the Tiger Owl, is a large owl native to the Americas. It is an adaptable bird with a vast range and is the most widely distributed true owl in the Americas.-Description:... , Siberian Tiger
Rachel Rachel (Animorphs) Rachel is a fictional character from the sci-fi book series Animorphs. Her full name is never explicitly mentioned in the books, but her relation to her cousin Jake Berenson through their fathers makes it most likely to be Rachel Berenson, if it was never changed or hyphenated.-Biography:Before the...	Horse Horse The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...	Bald Eagle Bald Eagle The Bald Eagle is a bird of prey found in North America. It is the national bird and symbol of the United States of America. This sea eagle has two known sub-species and forms a species pair with the White-tailed Eagle... , Cockroach Cockroach Cockroaches are insects of the order Blattaria or Blattodea, of which about 30 species out of 4,500 total are associated with human habitations... , Seagull, Horse, Great Horned Owl Great Horned Owl The Great Horned Owl, , also known as the Tiger Owl, is a large owl native to the Americas. It is an adaptable bird with a vast range and is the most widely distributed true owl in the Americas.-Description:... , Grizzly Bear Grizzly Bear The grizzly bear , also known as the silvertip bear, the grizzly, or the North American brown bear, is a subspecies of brown bear that generally lives in the uplands of western North America...
Tobias Tobias (Animorphs) Tobias is a fictional character from the sci-fi book series Animorphs written by K.A. Applegate. His surname is never mentioned, but had the Ellimist not altered time in order to take his father, Elfangor-Sirinial-Shamtul, back to his old life, his full name would have been Tobias Fangor, the...	Horse Horse The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...	Human Human Humans are the only living species in the Homo genus...  (himself), Horse Red-tailed Hawk Red-tailed Hawk The Red-tailed Hawk is a bird of prey, one of three species colloquially known in the United States as the "chickenhawk," though it rarely preys on standard sized chickens. It breeds throughout most of North America, from western Alaska and northern Canada to as far south as Panama and the West...
Cassie Cassie (Animorphs) Cassie is a fictional character from the sci-fi book series Animorphs, written by K. A. Applegate. Her last name is never mentioned, although she referred to it as being "nice" in The Secret.-Biography:...	Horse (Acquired a different type of Horse than her first (race)horse morph)	Osprey Osprey The Osprey , sometimes known as the sea hawk or fish eagle, is a diurnal, fish-eating bird of prey. It is a large raptor, reaching more than in length and across the wings... , Cockroach Cockroach Cockroaches are insects of the order Blattaria or Blattodea, of which about 30 species out of 4,500 total are associated with human habitations... , Seagull, Horse, Great Horned Owl Great Horned Owl The Great Horned Owl, , also known as the Tiger Owl, is a large owl native to the Americas. It is an adaptable bird with a vast range and is the most widely distributed true owl in the Americas.-Description:... , Wolf
Marco Marco (Animorphs) Marco is a fictional character from the sci-fi book series, Animorphs, written by K. A. Applegate. His last name is never mentioned.-Biography:...	Horse Horse The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...	Osprey Osprey The Osprey , sometimes known as the sea hawk or fish eagle, is a diurnal, fish-eating bird of prey. It is a large raptor, reaching more than in length and across the wings... , Cockroach Cockroach Cockroaches are insects of the order Blattaria or Blattodea, of which about 30 species out of 4,500 total are associated with human habitations... , Seagull, Horse, Great Horned Owl Great Horned Owl The Great Horned Owl, , also known as the Tiger Owl, is a large owl native to the Americas. It is an adaptable bird with a vast range and is the most widely distributed true owl in the Americas.-Description:... , Gorilla Gorilla Gorillas are the largest extant species of primates. They are ground-dwelling, predominantly herbivorous apes that inhabit the forests of central Africa. Gorillas are divided into two species and either four or five subspecies...
Ax Aximili-Esgarrouth-Isthill Aximili-Esgarrouth-Isthill is a fictional character from the sci-fi book series Animorphs.-Biography:Aximili is a young Andalite who becomes stranded on Earth when the Andalite Dome Ship GalaxyTree is shot down by Yeerk fighters...	Horse Horse The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...	Human Human Humans are the only living species in the Homo genus... , Northern Harrier, Horse, Great Horned Owl Great Horned Owl The Great Horned Owl, , also known as the Tiger Owl, is a large owl native to the Americas. It is an adaptable bird with a vast range and is the most widely distributed true owl in the Americas.-Description:... , Rattlesnake Rattlesnake Rattlesnakes are a group of venomous snakes of the genera Crotalus and Sistrurus of the subfamily Crotalinae . There are 32 known species of rattlesnake, with between 65-70 subspecies, all native to the Americas, ranging from southern Alberta and southern British Columbia in Canada to Central...