The source tells a whimsical story about Mount Haha-lua, a unique volcano on LavaLaff Island that erupts with laughter and desserts instead of dangerous magma. When the volcano suddenly turns grumpy and ceases its joyful displays, a young scientist named Penny is tasked with restoring its humor. By sharing lava-themed jokes with a disgruntled spirit named Groan, Penny successfully triggers a massive eruption of marshmallows and joy.