Beastologist-in-training Nathaniel Fludd and his Aunt Phil nurse a mysteriously ill unicorn, try to stop Obediah from taking the unicorn's horn, and finally get a solid lead on the whereabouts of Nathaniel's parents.
When Pinkalicious brings her imaginary unicorn, Goldie, to school and teaches him the rules, he helps her and the other students to become better friends.
Unicorns settle down with their bedtime routine by brushing their manes and ensuring their horns gleam before singing their song and drifting off to dream.