The Creeper sabotages the Core by destroying a main root which causes the animals to revert to their original language. The kids must find the origin spore that allows the animals to communicate.

The search for the Creeper leads Alex and Zoe to the Chamber of Legends, a dusty room filled with Animalian relics. Alex reveals that he helped a weasel escape from the tunnels, and only now does Alex learn that the weasel is none other than the notorious Creeper.

Livingstone calls an Animalian meeting to reveal that the Creeper is back. He journeys into the tunnels with Alex and Zoe to find it. However, the Creeper uses the Wind of No Return to foil the heroes' attempts.

Iggy is asked to babysit Echo while his parents, Erno and Elni, handle a portal-guarding shift. To entertain the baby elephant, Iggy tells him tales of Animalia in which Iggy is cast as the hero. But the Creeper sweeps Elni and Erno into the tunnels in order to kidnap Echo, whom the Creeper believes stands in the way of him controlling Animalia.

Tyrannicus plants a story that Livingstone is to retire. Livingstone refutes the rumour, but many Animalians believe Tyrannicus. When the Truth Corespore blasts off, Animalia can only speak in lies, so the kids must find the Corespore before Tyrannicus tricks Livingstone into quitting.

When nightmares plague Animalians, Alex and Zoe go to 'over and beyond', where they must find the Dream-Weaver and rescue Animalia from its dream troubles.

Livingstone and Reenie are struck by the 'glums', a rare Animalian version of the blues. There is only one cure for the syndrome: a good, long laugh. But those affected with the glums don't find anything the least bit funny, so Alex, Zoe, G'Bubu and Iggy must criss-cross the kingdom in search of the funniest joke in Animalia.

The Creeper is accused of stealing from the Animalians, but without any hard evidence, Livingstone refuses to blame it. Encouraged by Tyrannicus, the enraged Animalians rush into the tunnels. It's a trap, however, and they become stuck. Meanwhile, the Creeper tries to sabotage the Core but is thwarted by Allegra, the only Animalian not in the tunnels.

Alex bets Zoe that she can't resist talking for a full day. It's a vow of silence. So Zoe spends the day listening to the amazing and magical world of Animalia, and makes new friends and huge discoveries.

Alex and the gang put on a production of Treasure Island, but a corespore blows mid-performance, sending Animalia into a treasure hunt frenzy. Alex and Zoe journey to Over and Beyond to find the missing corespore.

Ever since Alex helped the Creeper escape from the portal, the boy has been wracked with guilt. He has the naive and unrealistic hope that he can convince the Creeper to turn over a new leaf.

When Alex and Zoe share a meal with the Horrible Hogs at the Elephants' Eatery they're appalled by the Hogs' awful table manners, crudeness, and limited social skills. The Hoity-Toity toucan overhears, and puts a spell on Alex and Zoe, making them Neanderthal versions of themselves.

Alex gets a video camera for his birthday and embarks on video research which turns into a hard-boiled detective documentary about the 'missing Melba'.

Once a year, Animalia celebrates with the traditional story-telling game known as Scary Story-Go-Round. Everyone in Animalia takes a turn to make up one continuous and very scary story.

Following the blueprints of the scientist Peter Applebottom, the Creeper has invented a device that can corrupt the Corespore. This turns all Animalians, including Alex and Zoe, into ninnies. Gorillas are the only species not affected by the corruption, so G'Bubu leads the quest to restore the Corespore and free Animalia from ninni-ness.

When pages disappear from Animalia's Big Book of Words, Animalians lose the ability to use the words on them. As their vocabularies shrink, the chaos in Animalia grows. Alex and Zoe must find why the pages are disappearing and restore the words to Animalia.

A Corespore blasts off and flies to the land of Over and Beyond, where fictional characters live. With this Corespore missing, Animalians are unable to agree about anything.

Alex and Zoe join forces to write a sci-fi story called Tomorrow. The story asks if the world was going to end tomorrow, what would you do?

Alex finds the Guardians of the Core Guidebook, which provides words and phrases that can help the Core. But when Alex isn't careful with the words he uses, the Core becomes a musical jukebox causing Animalians to sing and dance uncontrollably.

With the Creeper gone and peace restored to Animalia, Alex and Zoe decide it's time to go home. Livingstone also decides to take a much needed break, but before he can go, he must choose a new leader. Allegra and Tyrannicus vie for the position, but ultimately Livingstone knows that a good leader must lead with his heart.

After a few days in the 'real world', Alex and Zoe miss Animalia and want to return. But when they arrive, the city is in disrepair. They discover that time in Animalia moves at a different rate and a few days in their world is over a year in Animalia. Much to their surprise, G'Bubu and Iggy are no longer the leaders of Animalia, and instead King Tyrannicus is ruling the city.

The Creeper is back and he uses his knowledge of the Core to gain power and force the Animalians to do his bidding. Alex and Zoe are sent to protective custody, while G'Bubu and Iggy are searching the portals for Livingstone.

Livingstone is feeling unappreciated, but he gets the day off when a Corespore blast results in Livingstone turns into a happy-go-lucky twit.

Zoe and Tyrannicus join forces to shut down and drain the swamp. When Alex is struck with a swamp fever, Zoe puts aside her aversion and teams up with Allegra to track down the elusive plant.

Alex and Zoe are mistaken for monsters when they first arrive through the portal.