Pipo travels into underground Troll territory bearing gifts. He soon learns that Per's habit of chopping down trees caused the queen Troll Knakke to suffer terrible headaches. Eventually she left her underground home to take shelter in the ice palace up North. Pipo and Per decide to bring her back home. Despite being warned by a seasoned hiker, Pipo and Per are enchanted by an entire forest full of singing trees.
—The TV Archaeologist