To cure a sick townswoman, Allura searches for a flower that only blooms once every one thousand years. Haggar steals it to load Voltron into a trap, but Sven takes things into his own hands before Keith and the team arrive. He rounds up his band of freedom fighters and steals a skull tank, attacking Zarkon himself. Meanwhile, Lotor hatches a new plan to bring down his father with Merla's help.