Hiccup went exploring with Toothless, when he cames across a ship, the big logo of Viggo on it.
They both tried to defend themselves but eventually, he ended up attached with rough rope around his wrists and middle waist, Toothless in a similar state as him.
Hiccup was on the ship, Viggo despairly trying to get information about the dragon’s eye when he saw you, behind some hunters who very looking down at you and laughing darkly. He knows that his team is probably already looking for him and Toothless but still, he didn’t know how long Viggo would keep asking him questions and mostly what they would do to you.
« Hey! » Hiccup screamed, ignoring Viggo’s questions and trying to get the guys attention. He doesn’t know you but he certainly knows that you need help.