
15 plot points

Berk under dragon attack. Hiccup is a scrawny Viking who doesn't fit in, fails to help, causes destruction.
Stoick: "When you carry an axe, everyone around you is safer." Hiccup must prove himself, but in his own way.
Hiccup introduced to dragon training. His peers mock him. He learns about different dragon species and their supposed behavior.
Hiccup finds and confronts the Night Fury (Toothless) he shot down, but can't bring himself to kill it.
Hiccup secretly helps Toothless and creates a prosthetic tail fin. Should he reveal the truth about dragons or keep his secret?
First successful flight with Toothless. Hiccup enters a new world of friendship with dragons, defying Viking tradition.
Hiccup and Astrid's relationship begins to develop. She represents both the Viking way and potential understanding.
Hiccup uses knowledge from Toothless to excel in dragon training. Montage of flying, bonding, and discovering dragons aren't evil.
Hiccup wins dragon training. Astrid discovers Toothless. Romantic flight sequence - everything seems perfect. False victory.
Hiccup must kill a dragon in the ring. He tries to show dragons are peaceful but Stoick interferes, creating chaos.
Stoick disowns Hiccup ("You're not my son"). Vikings use Toothless to find the dragon nest. Hiccup loses everything.
Hiccup at his lowest point. Has lost his father's respect, Toothless is captured, Vikings are in danger.
Astrid rallies Hiccup. He realizes he must be himself and convinces the other teens to help. They ride dragons to save the Vikings.
Epic battle with the Red Death. Hiccup and Toothless work together perfectly. Hiccup sacrifices himself to save everyone.
Hiccup wakes up, has lost his leg but gained everything. Vikings and dragons live together. He's finally accepted and respected.