Uncover the secrets of the seven Gelfling clans with an inside look into the world of Thra from Jim Henson's The Dark Crystal: Age of Resistance, streaming on Netflix. Many trine ago, a song teller sought to explore the world of Thra and uncover the secrets of the Gelfling throughout the seven clans. Venture back in time with photos, sketches, and art from Jim Henson's The Dark Crystal: Age of Resistance in this exclusive, collectible book for Dark Crystal fans everywhere.