Arriving in Arboria, Flash and his friends are pursued through the forests by a lagre swarm of flying, poisonous Squirlons. Trying to evade the creatures Dr. Zarkov is bitten and almost immmediately the poison begins to take effect. As Flash, Dale and the rapidly faltering Dr. Zaekov encounter more dangers within the forest, Thun, Prince Barin and Vultan arrive to save them. In order to find the rare antidote capable of saving Dr. Zarkov's life, the heroes must brave the unknown dangers of the deep caverns...
