The Land Before Time All Grown Up VI: Secret of the Lost Valley is a 2024 theatrical animated sixth movie in the Land Before Time All Grown Up series
In the Great Valley that night, Littlefoot and his friends were telling stories about some dinosaurs and the herds even the other vallies and they all went to their homes in time to sleep.
At Littlefoot's home, Littlefoot had a sleep story about some dinosaurs he and his friends might encounted in different places even a lost valley he never seen before, and then he saw a giant flying creature that breathes fire.
In the morning the gang watches the clouds that shape things they see and when they went to get something to eat, they see some strange rocks that looks like 5 different dinosaurs and those mean the dinosaurs will bring back luck someday and they were thinking about that 5th rock that looks like a creature that Littlefoot saw in his sleep story and they think they might have more bad luck if they ever encounter one of them and somethings might happen to their valley if there's more bad luck until a huge twister came and made a huge mess of things and they and everyone have to clean all of it up.
At night, both Chomper and Ruby had sleep stories like Chomper encountering a rogue sharptooth on the bridge like log when it gives him bad luck and Ruby falling from a cliff while encountering a dinosaur when she gets bad luck, and at Ducky's home, Ducky had a sleep story about running from a dinosaur sliding from a hill when she gets bad luck, in Tippy's herd, Spike and Tippy both had sleep stories about encounting a rogue spiketail that gives bad luck, At Petrie's home, Petrie also had a sleep story about something might happen to him when he gets more bad luck when there's fire, and At Littlefoot's home Littlefoot had the same sleep story of the flying creature and discovers a strange lost valley and then got scared as the strange flying creature flies toward him and then woke up in horror.
In the morning the gang told each other that they all had sleep stories but Cera didn't and Littlefoot told in his sleep story that he saw a lost valley and the gang saw the dinosaurs that look like the rocks they saw meaning they might encounter them so the gang begin their journey to the lost valley and get pass the dinosaur that might give them bad luck.
When they reach to the cliff that Ruby saw in her sleep story, they encountered a tempered Tricky Fast Runner (Gallimimus) who wants them out of her territory, and Ruby was able to stopped her when she knocked her off the cliff and was about to fall before she was saved by a fast runner that looks like her but a blue male named Ovi and then continues to head toward the Lost Valley.
As they reach the forest, they meet a furry glider (Volaticotherium) named Glidy who was stuck in sticky sand and they tries to help them but some of them got stuck as well until they encountered three bad luck dinosaur, a four legged Sharpteeth (Ophiacodon) who gives them fear and Ducky was able to save them by getting a longest vine and pulled them out with Littlefoot's help and the the four legged sharpteeth tries to attack them,but they missed and got stuck in the sticky sand as they stick to the bottom and the gang were all out of the pit with their new furry friend and continues to move on.
When they left the forest there was sky water coming down from the sky and a storm caused the fire and they were able to reach high land to escape from the fire.
At night, the gang enters the trees where they stopped to rest before they can continue to move on, and Cera started to have sleep stories about a shadowy creature that was chasing her and she fell into the pit and woke up scared and woked up the others then went back to sleep.
In the morning the gang woke up and continues to head towards the valley and as they enters the woods they encountered a really bad tempered Triangle Plated Spiketail (Tuojiangosaurus) who hates trespassers and Spike and Tippy were able to distract him long enough for the others to escape as they slide down a hill in the mud slide far away from the tempered spiketail and as their safely slide down to the ground, Petrie gets worried about more bad luck as Spike and Tippy will able to prevent their friends from getting hurt and then set moves on.
When they moved on they entered a meadow of jumping water and then face off against a Dangerous Sharptooth (Ostafrikasaurus) and starts running towards the bridge like log that Chomper saw in his sleep story and they all will able to get across and Chomper tricked the sharptooth by making him try to eat him but the sharptooth bit the log and after Chomper made it off the log the Sharptooth meets his death as he fall into the pit, then Littlefoot spotted the lost valley he saw in his sleep story and the gang head towards.
As they were about to head towards the valley they encountered a herd of horned domeheads (Dracorex) led by Drasari and then brought them to the rest of the herd led by his father D'Draca who been trapped in the lost valley because of the flying creature that breathes fire and notice that it has to be the monster Littlefoot saw in his sleep story and he and his friends must help them find a way to escape without being caught.
Meanwhile back in the Great Valley, bad luck starts happen when all the dinosaurs came when they had problems with and Mr.Thicknose wonders if Littlefoot and the others found the problem.
When Littlefoot explores the valley he sees the lone dinosaur Doc and his wife Dara who now has a son name Loner and then he saw his grandpa's old friend and story seeker Saro who was on his way to meet up with his grandpa and when they gang showed up, they were surprised to see Doc and Dara, their son and Saro when they haven't seen them over the past years and then they head off to find place to rest before they can help the herd escape from the Flying Monster.
At night time Littlefoot starts having another sleep story about what will happen to him and his friends and all the dinosaurs if the every encounter the flying monster and woke up and then at dawn he saw a creature in the bushes and happens to be Hidden Runner who woked up the others as well.
In the morning the herd was about to leave the valley as fast as they can before the flying monster wakes up and tries to get them,but Littlefoot and his friends have a plan to keep the flying monster busy long enough so the herd could escape, and then Littlefoot was tricking the flying monster by leading him to close to the water when the monster tries to eat him and then missed and tries to breath fire, but all the water in his mouth gotten rid of all the fire and then Littlefoot and his friends had help from Drasari and Saro along with Doc to defeat the monster, and then they all defeated him by causing the rocks to breaks one of his wings and got him crushed by a huge pile of boulders and the flying monster is dead.
After the monster was defeated, Saro set off to catch up with Littefoot's father along with Doc and Dara and their son and then say goodbye to Littlefoot and the gang, and Drasari and his father thanks them for giving their freedom and then moves on with their herd, and the gang starts saying goodbye to Ovi who is continuing his long journey and they all head back to the Great Valley along with their new friend Glidy and Hidden Runner.
When the gang back to the Great Valley, Mr. Thinknose was surprised to see Hidden Runner again and made Glidy a new member of their home and Littlefoot told Mr. Thinknose that they saw Doc and Dara and their son and his Grandpa's old friend Saro and put an end to bad luck by dealing with the dinosaurs.
Later, at night, the gang tells stories about how they deal with the bad luck dinosaurs including the flying monster they defeated and when they met a herd of Horned Domeheads and how they met new and old friends and Ruby was hoping to see Ovi again someday.
Special Guest Stars
Jack McBrayer as Ovi (Oviraptor)
Cherami Leigh Glidy (Volaticotherium)
Phil LaMarr as Drasari (Dracorex)
Morris Chestnut as D'Draca (Dracorex)
Back Luck Dinosaurs
Tricky Fast Runner (Gallimimus)
Fearful Four legged Sharptooth (Ophiacodon)
Triangle Plated Spiketail (Tuojiangosaurus)
Dangerous Sharptooth (Ostafrikasaurus)
Flying Sharptooth Monster (Prehistoric Dragon)
Horned Domeheads (Dracorex)