Here is the plot summary for How to Train Your Dragon: The Hidden World: As Hiccup, now a confident and compassionate leader, works to establish a harmonious coexistence between dragons and Vikings on Berk Island, his trusty dragon partner Toothless embarks on an unexpected adventure. While exploring the skies, Toothless stumbles upon a mysterious, untamed Night Fury female, and his primal instincts kick in. Hiccup's best friend, Astrid, is initially thrilled about the prospect of Toothless finding a mate, but as the situation unfolds, she realizes that this newfound connection may put their entire community at risk. As tensions rise on Berk Island, Hiccup's leadership is tested when he must confront the return of the Grimmel, a ruthless dragon hunter with a personal vendetta against the Night Fury. With his dragons and Viking allies facing unprecedented threats, Hiccup must come to terms with Toothless' newfound independence and find a way to protect their island home. As the stakes grow higher, Hiccup and Astrid embark on a perilous quest to uncover the secrets of the hidden world, where ancient dragon wisdom may hold the key to their survival. With the fate of Berk Island hanging in the balance, the beloved duo must confront their own limitations and the changing nature of their bond with Toothless. In this thrilling conclusion to the How to Train Your Dragon trilogy, Hiccup's growth as a leader is put to the ultimate test as he navigates the complexities of love, loyalty, and the unbreakable bonds between humans and dragons.