Chomper's cave starts leaking, so the gang searches for a new cave Chopper can stay in while he lives in the valley.
Cera accidentally loses Tria's shiny stone, so the gang travels to the Canyon of Shiny Stones looking for a new stone to replace the lost one.
Ruby and Chomper tell the other kids about a place where water jumps out of the ground, and they head out to see it. Meanwhile, Petrie frets that the tree stars Spike ate will bring them bad luck.
One night, Ruby tells the group a scary story about an invisible dinosaur named 'Hidden Runner and gives everyone scary sleep stories. They see Mr Thicknose to tell him that she made up the story and there is nothing to worry about, but the story of Hidden Runner was true, and they decide to venture into the Mysterious Beyond to search for him.
Ruby's first Star Day (her birthday) in the Great Valley has Ruby missing her family. But when the other kids decide to throw a surprise "Giving Ceremony" to make Ruby feel better, their secretive preparations result in Ruby feeling even lonelier!
Ali's herd returns to the valley, and a new dinosaur named Rhett claims sharptooth's fear him, so the gang decides to bring in Chomper to see if he is a liar.
Ducky invents a new game while trying to get a tree sweet, and now everyone is anxious to see who can win the log-running cmopetition.
Everyone except Cera and her father are excited for the bright circle celebration, but when fire threatens everyone only Cera and her father can save the day.
The series finale. Littlefoot, Ducky, Petrie and Chomper (followed by Hyp, Nod and Mutt) find a nest of Fast Biter eggs. They decide to carry the eggs away from the valley so the baby sharpteeth can grow up without eating anyone and set off on a journey into the mysterious beyond. They don't know that the mother sharptooth is in hot pursuit though, and she wants her eggs back at all costs.
An earthshake traps Ducky and Chomper on a ledge with the sharptooth Thud, who is pinned down by rocks. In the end, Chomper and Thud discover which of them is the "bigger" sharptooth!
It's lonely being the only Sharptooth in the Great Valley. Chomper decides to go to the Mysterious Beyond to teach the Sharpteeth how to be friends. But the Sharpteeth he meets aren't very friendly, as he soon runs into Red Claw and his Fast Biters!
While trying to learn how to fly Guido is blown into a cave with Petrie, and they encounter a blind old flyer called Swooper.
A freeze has come to the Great Valley, so Mr. Thicknose decides to tell everyone about a mysterious treat known as Hard Water Sweets (which are frozen grapes). The gang desires to taste this treat, so the embark on a journey to find them.
When Spike falls down a hole, he encounters a colony of mammals who thinks of him as the 'Big One' from the Mysterious Above. Meanwhile, his friends try to save him but only find trouble when Mr Thicknose and Topsy can't agree on what to do.
A herd of sand creepers (crabs) comes to the Great valley, so the gang decides to investigate why they are there.
Tippy and his family return to the great valley, much to Spike's delight. But a dispute over food leaves them being forbidden to play with one another.
A rainbow is mistaken as being sky stones. When it disappears, the gang decides to see where it has run off to.
When Cera accidentally makes falling rocks scare away a group of Belly-Draggers, the dinosaurs think she is a hero. Cera loves the attention, but things get out of hand when the Belly-Draggers return.
A storm destroys Petrie's nest, and Ducky tries to teach Tricia how to swim.
On the day of the Falling Rocks of Many Nights (meteor shower), Ruby remembers a memory of her family meeting at Hanging Rock when she lived in the Mysterious Beyond. Ruby adventures alone to find her family, but her friends come along to help. They meet Skip along the way, a mammal who knows the Mysterious Beyond very well, and the gang learns an important lesson of being family.
The gang tries to find someone who can help explain why Chomper has lost a tooth to see if it's normal.
After an earthshake dries up the fast-water, the dinosaur kids try to fix the problem by removing the rocks. On the way, they meet their old friend Mo.
Doc returns to the great valley, in search of a lady friend. But when he finds out Littlefoot is friends with a sharptooth, their friendship gets strained.
When Grandpa Longneck's old friend Saro comes to visit, the kids discover that Grandpa used to be a legendary Story Speaker.
