The Land Before Time X: The Great Longneck Migration (2003)

Plot
Littlefoot has an ominous "sleep story" (dream) where he sees the "Great Circle" (the sun) falling out of the sky, and when he mentions it to his grandparents, they reveal they are sharing the same experience, with his Grandpa lamenting that they need to go somewhere. Led only by their instinct, they leave the next day. Out of curiosity, Cera, Spike, Ducky, and Petrie follow them. During their trek, Littlefoot is nearly eaten by a Sarcosuchus while playing in a swamp, but a Supersaurus named Sue saves his life by stepping on the predator and joins him and his grandparents, as she is driven on by the same sense as them. The group is soon joined by dozens of other Longnecks feeling the same instincts. Meanwhile, Littlefoot's friends are attacked by the Sarcosuchus in the same swamp as before, but they manage to escape. Afterwards, they sleep next to a large boulder, which the next morning, turns out to be a sleeping Sharptooth (a gray Daspletosaurus), which wakes up and chases them. They escape into a small cave and meet Pat, an elderly Apatosaurus.

Littlefoot's herd reaches a large crater where hundreds of Longnecks have gathered. There, he meets his long-lost father, Bron, for the first time. After been separated from his mate in an earthshake, he has become guardian to a young, mischievous Brachiosaurus, Shorty, who becomes jealous of Littlefoot taking all of his father's attention. Meanwhile, Pat shares to Littlefoot's friends that the Longnecks are being driven by a tradition involving a solar eclipse, which was taken as a sign that the sun will be sent crashing down into the Earth by the "Night Circle" (the moon). Every solar eclipse, Longnecks from all around the world gather in one location to stretch their necks up and "catch" the sun, so they can propel it back up into the sky. Soon after, Pat steps into a pool of lava, which scalds his leg, but he is still able to move as they escape the lava field.

On the day of the eclipse, Littlefoot wakes up to see Shorty traveling over the crater walls and running away, out of spite for being ignored by Bron. He catches up to Shorty and convinces him to stay; the two reconcile and agree to see themselves as brothers. Moments later, as Littlefoot reunites with his friends, a brown Daspletosaurus appears and attacks the group. Pat defends the children but is slowed down by his burned leg. Bron rushes to their aid and defends them from the Sharptooth and is nearly killed, but Pat saves him. Pat and Bron manage to overpower and temporarily knock out the brown Sharptooth. Then the gray Daspletosaurus and a green third Daspletosaurus arrive. Littlefoot's grandparents join the fight and defeat the green Sharptooth. Bron fights the brown Sharptooth again while Pat fights the gray one. As soon as all three Sharpteeth are defeated, the eclipse begins, and the sudden darkness scares away the Sharpteeth towards the end.

Littlefoot, his grandparents, Bron, Shorty, Sue, and Pat take their place among the other Longnecks, who have all gathered on top of the crater walls. They succeed in "catching" the sun, and everyone rejoices as the eclipse ends. With their mission completed, the different Longneck herds depart on their separate ways. Sue departs with an Ultrasaurus. Littlefoot's friends ask Pat to come live with them in the Great Valley, which he accepts. Littlefoot is initially hesitant in leaving Bron, as he is the leader of a migratory herd, but he eventually realizes that he belongs in the Great Valley. Accepting this, Bron leaves with Shorty and his herd, promising to keep in touch with Littlefoot and visit him. Littlefoot returns to the Valley with his friends, grandparents, and Pat.

Voice Cast

 * Alec Medlock as Littlefoot
 * Kiefer Sutherland as Bron
 * Kenneth Mars as Grandpa Longneck
 * Miriam Flynn as Grandma Longneck
 * Aria Curzon as Ducky
 * Jeff Bennett as Petrie
 * Rob Paulsen as Spike
 * Anndi McAfee as Cera
 * Brandon Michael DePaul as Shorty
 * James Garner as Pat
 * Bernadette Peters as Sue
 * John Ingle as Narrator/Topsy