The Land Before Time X: The Great Longneck Migration is a 2003 direct-to-video animated adventure musical drama film and the tenth film in the Land Before Time series. 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. Littlefoot explains his situation to his friends and they become interested. 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. They are soon joined by dozens of other Longnecks feeling the same instincts. Meanwhile, Littlefoot's friends are attacked by the Sarcosuchus in the same swamp that Littlefoot and his grandparents passed through, but they manage to escape. That night, they sleep next to what appears to be a large boulder. The next morning, they discover that the "boulder" was a sleeping gray Tarbosaurus, which wakes up and chases them. They escape into a small cave and meet Pat, an elderly Apatosaurus. Littlefoot, his grandparents, and Sue reach a large crater where hundreds of Longnecks have gathered. There, he meets his long-lost father, Bron, for the first time. Bron tells Littelfoot how he was separated from Littlefoot's mother during the great "earthshake" (earthquake) in the first film. During his wanderings in search of Littlefoot, Bron became the leader of a herd of longnecks and the guardian to a young, mischievous Brachiosaurus, Shorty, who becomes jealous of Littlefoot taking all of his father's attention. Meanwhile, Pat tells 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 burns his leg badly,