In "How To Train Your Dragon: The Hidden World," the story follows Hiccup, a young Viking, and his dragon, Toothless, as they seek a safe haven for their kind. The film explores themes of friendship, bravery, and the bond between humans and dragons, as they face new challenges and adversaries. As Hiccup strives to protect his village and the dragons, he discovers the existence of a mythical place called the Hidden World. This secret realm serves as a sanctuary for dragons, leading to a journey of self-discovery and the importance of letting go for the greater good.