In a village populated by birds, two young hummingbirds embark on a search to find their friend. When they locate him, they discover that he was not lost at all, but has been the victim of an unknown illness. The young birds are determined to find the source of this ailment. They discover that the problem is a hummingbird feeder whose liquid has fermented, thus creating a toxic, near poisonous mixture. They must find a way to inform the person responsible for the problem. The solution is found in a book at the game warden's home and they proceed to deliver it to the owner of the feeder in question.
Niki is comfortably sleeping in his nest when Viki arrives and wakes him with a start. Viki is in a panic. She has a bad feeling that something terrible has happened to Timmy - he never returned home last night. None of the other characters in the village seems very worried; they think Timmy's disappearance is related to his normal moodiness. Viki remains convinced that Timmy is in trouble and talks Niki into helping her find him.
The two young hummingbirds speak to everyone in the village. Someone tells them that he last saw Timmy playing near the house.
The two young birds go to the house and see Timmy lying on the ground. He looks hurt. As they get nearer to their friend, the cat rushes in and grabs Timmy, taking him to an unknown location. The two buddies must go on a cat hunt to find Timmy. They eventually find the cat close to the camp, with Timmy lying on the ground close by. Viki and Niki must get the cat away from Timmy in order to save him.
With the cat finally out of the way, the two friends reach Timmy and take him back to the village. Believing that the cat attacked Timmy, the villagers revolt.
Timmy awakens and claims to have fallen ill. However, he cannot remember any other details to explain his current state. He doesn't even remember where he was.
The two friends look for the source of the problem. The blue jay is convinced that the cat is to blame - he declares war against the cat.
Places where they may find clues:
- The Wise Tree provides information that is almost impossible to understand.
- Viki's grandfather talks about an epidemic of sick birds in his youth. No one ever knew the reason behind it and no cure was ever found.
- The crows who live in the swamp consider themselves superior because they were not affected by the epidemic.
- The frogs know nothing.
- The magpie does not seem to want to help and only wants to gather information.
- The cardinal doesn't want to be bothered.
- Timmy has lost his memory.
- The game warden knows nothing, but offers to do research on the subject. That's why the book is opened at the right page.
After speaking to everyone, Viki suggests a radical solution: "Let's go ask the cat!" Once persuaded, Niki gathers his strength and looks for a way to capture the cat so he can be questioned.
The two birds discover that the cat is not nasty and even wanted to help Timmy. The cat admits that he admires the hummingbird's beautiful feathers. He also informs them that he saw Timmy drink from the feeder near the house and drop to the ground shortly thereafter. With this new information, the Tree is able to provide more information by discussing the phenomenon of fermentation. They learn that if nothing is done, every hummingbird that drinks from the feeder risks illness or worse, death.
The two young hummingbirds now look for ideas to inform the owner of the house. The various characters offer ridiculous suggestions that are all rejected by Viki.
Entering the game warden's house, the two discover a book open to a page on hummingbird feeders. With the game warden absent, the birds borrow the page, intent on getting Mrs. Rivers to read it. The final decision is to pin the page on the post holding the fermented birdfeeder. However, before Mrs. Rivers gets a chance to fill the feeder, the wind tears the page off the post and blows it up in the air. When all seems lost, the game warden suddenly appears and grabs the page. He's been looking for the hummingbirds ever since he discovered the information in the book. Upon finding the missing page and the note left, he rushes to Mrs. Rivers' house to explain the problem.
Upon their return to the village, the young hummingbirds find that Timmy is well again and that everything in the village is under control until the next adventure!