Avatar - Series 1 - Episode 1
While fishing, siblings Katara and Sokka discover Aang, a young boy frozen in an iceberg. After freeing him and his flying bison named Appa, they learn his identity as an airbender, long thought extinct, and bring him back to their village in the Southern Water Tribe. After witnessing the beam of light that shot through the sky after the two broke through the ice, Zuko, exiled prince of the Fire Nation tasked with finding the long lost Avatar to restore his honor, becomes intent on capturing him.