Jen is the main protagonist of The Dark Crystal. He is a Gelfling whose clan was killed by the evil Skeksis. He was taken in by the gentle Mystics and is sent on a journey by his dying master to save his home planet.
Jen wears a pale, cream-colored tunic with UrRu designs. His skin has a slight brown complexion and his hair is dark with fair (almost silver) streaks, which grows to shoulder-length.
Jen was a member of the Gelfing race, thought he was the only known survivor of the Garthim massacre. Jen lived most of his life in the Valley of the Mystics, whose master assigned him the task of completing his dying wish to have the missing piece of the Dark Crystal restored, ending the evil rule of the Skeksis. Jen sets out, where he meets Kira, a fellow Gelfling survivor who had spent her life among the woodland creatures and animals of the Podlings. With the missing piece of the crystal in hand, Jen, Kira and Fizzgig, take on the evil Skeksis and heals the crystal.
- Jen is often shown to carry with him a small double-pronged flute called a Firca, which he plays.