Family on the Edge.Hiccup and the riders are preparing an attack on a hunter shipyard when Dagur appears, asking for Hiccup's help to find Heather. Though still doubtful, Hiccup and the others scramble to keep the siblings from noticing each other by sending Heather away while offering Dagur a Gronckle he names Shattermaster to get him to leave, but they cross paths anyway. Dagur, despite his pleas that he is trying to change, is imprisoned once he sees the riders' plans and warns Hiccup that the shipyard is a trap. The riders, Heather in particular, refuse to listen and head in anyway, leaving Dagur to take charge and sacrifice himself to allow the riders to escape. Back at the Edge, Heather finds a note from Dagur telling the truth about their father, leaving Heather to mourn in silence.