Jack is the titular protagonist of Jack's Big Music Show.
Jack is a mouse-like creature and the star of the show. Every day, Jack gets to spend his own special time in his favorite place in the world: his backyard clubhouse. It's here that Jack meets up with his best friend Mary, and his dog Mel, to do what he loves best: make music, sing, dance, and have a great time! Jack's interest in learning all kinds of music leads him to discover melodies in the most unpredictable places, like finding rhythms in raindrops and musical tunes from tiny bugs. To Jack, music is the greatest. There's always something unpredictable going on in the clubhouse and Jack has a way of using music to save the day.
Jack is blue with a black nose. He wears an orange shirt with a red asterisk in the center. His pants are a brown color.
Jack appears in every episode of Jack's Big Music Show. His first appearance was in Little Bad Wolf and his last appearance was in Jack and the Beanstalk.