Uncle Bill is Dr. Snuggles' uncle, an explorer, who "goes to lonely parts of the world, discovers unknown rivers, climbs mysterious mountains, and looks for strange animals".
The horrible, horrendous Snarky Quark is a giant, furry monster who lives in a strange land made entirely of rock. In the end, he is really nice but afraid of mice. He also likes to eat rock which is why he has a terrible toothache.
Great White Llama
Great White Llama is the oldest and wisest animal in the Amazon jungle. He lives by the Amazon river in an ancient marble temple.
Nitpick: In previous episodes to find someone with the Multi-Whereabouts Machine, Dr. Snuggles has given the machine something belonging to the person he is looking for so that the machine can get his or her "scent". In this episode when he looks for Uncle Bill, he doesn't give the machine anything of his. It's possible that the machine can still find him because Dr. Snuggles knows Uncle Bill is somewhere in the Amazon jungle.
Nitpick: Nita Parakeeta's accent is more Spanish (or even Mexican) than Portuguese. Even though the Amazon jungle is in Brazil, where Portuguese is the official language, it's possible that Nita isn't originally Brazilian but from somewhere else in South America.
In the opening credits on the scroll of parchment the title of this episode is written as The Unbelievable Wormmobile Adventure. However, in every episode listing and on the back of the DVD box set, it appears as listed here.
Cosmic Cat comes from another planet. He arrived one night in a cat-shaped spaceship and now lives with Granny Toots in her cat hospital. He talks in enigmatic riddles and possesses psychic powers.
Granny Toots lives in a giant beech tree with all her cats. She is one of Dr. Snuggles' oldest and dearest friends and runs a cat hospital which is built into a greenhouse.
The Mustard Bush
Even though he doesn't speak in this episode, you can see the Mustard Bush standing across the road from the Treacle Tree near Rickety Rick.
Goof: When Dr. Snuggles and the gang finally find Miss Nettles in the castle, Peter Ustinov mispronounces her last name as "Nettle" instead of Nettles.
It is revealed that Professor Emerald's first name is Erasmus.
Nitpick: In this episode the Treacle Tree ang his companion, the Mustard Bush, seem to be living both outside Dr. Snuggles' house and outside Rickety Rick. But Rickety Rick isn't near the house, in fact, it's a walk away. Perhaps the trees migrate from time to time?
Ray the Radio
Ray is Dr. Snuggles' radio. He knows what the weather is going to be like, plays music and also keeps Dr. Snuggles up-to-date with his announcements.
Woogie the Freckled Camel
Woogie lives in the Lavender Lullaby, a huge pink cloud which is in the pink stripe of the Rainbow. His favorite pastime is drinking tea.
The flock of Lavender Sheep also live in Lavender Lullaby, guarded by Woogie the Freckled Camel. When they speak, you will instantly begin to feel very sleepy.
Skybed Fred is a vicious space pirate who sails the skies in his bed. He and his navy of fellow pirates challenge their enemies to pillow fights.
The forest where Dr. Snuggles and all the animals live is called Snugwood.
Dr. Snuggles' bossy housekeeper.
Dennis the Badger
Dr. Snuggles' friend and assistant. He operates the Badger Graph to draw the schematics to Dr. Snuggles' various inventions.
A mischievous little mouse who is always causing all kinds of trouble. He lives in Dr. Snuggles' kitchen and is obsessed about cheese.
Dr. Snuggles' faithful pocket watch who reminds him what time it is.
Dr. Snuggles' talking duck-head umbrella/pogo stick. Although he is introduced in this episode, his name is not revealed yet.
Dr. Snuggles' talking, walking tool shed where he and his animal friends invent all sorts of machines. Rickety Rick can also turn into a boat.
Miss Nettles' pipe-smoking, aristocrat friend. She also owns a dog, a greyhound named Lord Louis.
Ringo & Tingo
The two mice who wear blue and red overalls are Dennis' little helpers.
The sleepy messenger bird who delivers letters and mail in the forest where Dr. Snuggles lives.
Benjy & Freddy
Benjy & Freddy are Dr. Snuggles' two rabbit friends. They help him on his adventures.
Quiffy, Quaffy and their family
Quiffy and Quaffy are a duck couple. Quiffy wears a navy uniform and Quaffy wears a green-and-blue dress with a matching bonnet.
Hugo the Frog
He lives in the pond near Rickety Rick.
The Multi-Whereabouts Machine can be used to locate anything or anyone anywhere in the world. It needs to be given some kind of clue to help it find what it's looking for. In this episode Dr. Snuggles uses Miss Nettles' handkerchief to find her.
The Badger Graph
Dennis the Badger uses the Badger Graph to draw the schematics of Dr. Snuggles' inventions so that they know what parts they need before they start building the invention. The Badger Graph is made of a drawing board, a pen, and levers to move the pen around the board.
Mathilda Junkbottom is a housekeeping robot that Dr. Snuggles invented as a present for Miss Nettles to help her around the house.
Junk-O-Scope is a stethoscope of sorts, used to examine what's wrong with Dr. Snuggles' machines.
It is revealed that Miss Nettles' first name is Hilda.
Goof: When Miss Nettles climbs up after falling into the pond, her clothes are not wet. The same thing happens again when the house is flooded.
Goof: When Miss Nettles is reading the letter aloud to Madame Dumpitoo, her lips are not moving.