Taking place during How to Train your Dragon 2. Sadie is part human part night fury. She was an experiment made and enslaved by Drago. But she escaped and was living in the woods. Eventually she befriended Toothless and they stuck together for a while taking care of each other. when one day toothless was struck by a net. Hiccup decided against killing toothless and befriended toothless and found Sadie and befriended her. Hiccup was the first person Sadie could trust, becoming a brother to her. When Stoic found out about toothless and Sadie he used toothless to find the alpha and locked sadie away. Astrid, was very wary of Sadie and did mot help her oit at first but soon realized her mistake and that Sadie was just a kid like her. Astridand the others then helped Hiccup and Sadie get toothless back and defeat the alpha from How to Train Your Dragon 1. After Hiccup proved that dragons were friends rather than enemies to the vikings and to Stoic, dragons and vikings were living in harmony on Berk. Until a new threat arises. Drago Bloodfist, Sadies creator was coming to collect and control all the dragons using an alpha, his bewilderbeast to control them. With the team, and Hiccup leading, Sadie will help them defeat this new threat. Along the way hiccup will find and meet his mother Valka who went missing 20 years ago, presumed dead, when she was really alive at a sanctuary she created for dragons. Valka will take an interest is Sadie and become caring for Sadie like the mother she never had. And along the way, love will spark with Astrid and Sadie. Hiccup and toothless are sadies best friends. Hiccup is like a brother to sadie.