Holly whines to Dad that she doesn't want to go on the overnight trip with him and Will that is necessary to complete their pylon map. She would rather work on the dress she is making, but Dad feels uncomfortable leaving her all alone. Holly makes the case that Dad is always trying to get his kids to be more self-sufficient, and the only way she can become so is with an opportunity like this. Dad quiets Will when he takes Holly's side, but then gives in providing his daughter abide with one condition: that she invite Cha-Ka over to stay the night. Holly is offended that she has to be "baby-sitted" by Cha-ka, and snaps at her brother when he teases her by feeling sorry for the little Paku. Dad puts a quick end to his childrens' arguing, and allows Holly to stay if she keeps near High Bluff. He instructs his daughter to make a smoke fire in the event that she should get into any trouble; he promises that Will and he will stay close to high ground, allowing them to see the smoke and rush right back. Will puts up a stink about Dad's promise to rush back, whining that they will end up coming to Holly's rescue every 15 minutes. Holly agrees to Dad's plan, claiming that she won't be afraid, but Will tries to frighten her by warning her about Zarn. He does his best to get her scared about the creature, mentioning his spooky appearance, telekinetic and mind probing powers; he then finishes by saying sarcastically that Zarn is nothing to worry about. Dad assures Holly that her brother is just putting her on, and after more teasing by Will, Dad double-checks the plan with his daughter. Dad and Will head out, but Will pops back in to tease his sister one last time. When he sarcastically adds that Zarn "has probably forgiven us by now for wrecking his starship", Holly vengefully throws a metal pot at her brother. Out in the Mist Marsh, however, Zarn rummages through his ship's debris and scoffs at the idea of forgiving the Marshalls. (How could Zarn have read Will's mind from so far away? If he could, why did he previously send Sharon out to observe them?)

Zarn strolls through the jungle, where he comes across Grumpy; he mocks the carnivorous beast's relative stupidity. He flaunts his inaccurate knowledge, making the unsound claim that after a million more years of evolution, tyrannosaurs will turn into birds. He then toys with Grumpy by somehow causing the beast to be plagued with intolerable itching.

Holly is relaxing back in their cave when Cha-Ka comes along; he explains to Holly that he is being chased by Ta. He asks if he can stay with Holly, so she invites him in to have some dinner. When Cha-Ka starts eating the salad with his hands, Holly pleasantly instructs him to use his fork. He then tries stabbing a large piece of lettuce, but Holly advises him to cut it up with his knife. Cha-ka just uses the knife like another fork, so Holly switches to something else by offering her guest some bread. Cha-Ka uses his fork and knife on the loaf, but throws down his utensils, frustrated and confused, when Holly tells him to use his hands. As Zarn lurks around the base of High Bluff, Holly hears the tinkling wind-chime sound; Cha-Ka didn't hear any such noise, so Holly decides that it must have been her imagination. Zarn comments to himself that reason Cha-Ka does not hear him is because the Pakuni mind is too primitive.

After their meal, at the base of the bluff, Cha-Ka watches Holly washing the dishes. She asks him if the Pakuni wash their dishes, but Cha-Ka demonstrates that they simply throw them away (no way would the Pakuni go to the trouble of making a bowl, only to discard it after a single use). Holly asks the little Paku to go get the bowl, but each time he tries to pick it up, it jumps a few feet out of his reach. Cha-Ka runs back to Holly, babbling about "oganza" (magic); she calls the Paku silly, but changes her mind when she hears Zarn's tinkling. She decides to work on her dress to make herself feel better, using Cha-Ka to model the garment. As she hems the already short leather dress (Dad would never approve of her wearing the kinky item), she and Cha-Ka are startled by Ta's burst of laughter. Holly harshly demands to know the purpose of Ta's arrival; the angry Paku calls himself "fierce leader" and has come to fight with his clansman Cha-Ka. Holly calls Ta a bully, and declares that there will be no fighting, but Zarn telekineses an open melon into Ta's face, then into Cha-Ka's hands. Holly scolds Cha-Ka for doing such a thing and orders him up to the cave to take off her dress. Ta tries climbing up after Cha-Ka, but Holly pushes him tumbling back down.

Later, while Cha-Ka and Holly are up in the cave, Ta calls for Cha-Ka to come down and fight. Holly at first tells Cha-Ka not to worry, but then Ta calls out that Cha-Ka must come home sooner or later. She realizes that the little Paku must eventually confront the bully, so she gives Cha-Ka some lessons on footwork and fist-fighting. She tells him to be brave like when he tossed the melon into Ta's face, but Cha-Ka flatly denies having done the deed. He claims that it was magic, which Holly at first scoffs at, but when she hears Zarn's tinkling and sees items mysteriously falling off a rack, she realizes who is responsible for the pranks. Without hesitation, she storms out of the cave to confront the mischievous, nearly invisible being.

At the base of the bluff, Holly calls out for Zarn to show himself and take responsibility for his actions. She confidently insists that she is not afraid, and holds up well to Zarn's taunts of echoing her words in her own voice. Zarn compliments Holly for holding her ground, amazed at her cunning for being the "baby of the family". Holly takes offense at being called a "baby", and when Zarn rephrases by calling her the youngest child, she goes on to accuse him of acting childishly. Zarn makes the claim that he is performing research, but Holly considers his explanation dubious. She gets all upset that he is being cruel to Cha-Ka, causing Zarn to turn red and plea for Holly to control her feelings. She apologizes, having forgotten that her father told her of the being's condition, but Zarn gripes that his own intelligence evolved over 1000 years is not properly referred to as a "condition". Holly pleads to Zarn to use his powers in a constructive way, such as granting Cha-Ka the courage to fight brutish Ta. Zarn points out that courage derives from the assumption of success, so Holly rephrases her request into asking Zarn to help Cha-Ka win. Zarn admits that he has the power to do so, but argues that Ta is the Pakuni leader due to his greater height and weight. He argues that Cha-Ka would surrender his leader status within a day, but Holly gets upset, since she believes otherwise. Her flaring temper turns Zarn red and doubled over in pain; Holly goes stomping up to the cave, metaphorically asking why Zarn cannot be nice if only once.

Holly and Cha-Ka are taking a nap up in the cave when they are awakened by Ta, who has returned to fight Cha-Ka and calls out for him to come down. Ta calls Cha-Ka an "ekonga", literally "iguana" but meaning "chicken" or "coward", so Holly informs Cha-Ka that he now has no other choice but to fight. The little Paku is frightened, but Holly demonstrates once more the art of fist-fighting footwork, and as she walks him out of the cave, she reminds him to be brave and manly. Cha-Ka's bravery falters, and he tries to run back up to the cave, so Holly tries desperately to give him some encouragement. Ta approaches Cha-Ka, who then huddles down and covers his head, so Zarn uses his powers to uproot a bush and knock Ta over with the ball of dirt that clings to its base. Ta goes somersaulting backwards and then flees into the jungle. Holly congratulates Cha-Ka, calling him an "obimi abisa" ("great man"); she grabs a laurel vine from the jungle and fashions it into a crown for the victorious Paku. After she bids Cha-Ka goodbye, Holly thanks Zarn who has just reappeared. When Zarn fails to show any pride for granting the good deed, Holly asks the being if he does not feel good deep inside for doing so. Zarn replies that he is fortunate to be free of such emotions, but Holly maintains that the being simply refuses to admit that real feelings lie beneath all of his pranks. Zarn then levitates a melon to hurl at Holly, but lowers it back down when she emotionally commands him to stop. Her reaction turns the being's sparkles red, prompting Zarn to beg Holly to feel nothing; she agrees to hold back the emotions if he will stop the research. After the being agrees, Holly asks him why he was researching Cha-Ka; she is surprised to find out that she was the one being studied. Zarn then bids Holly goodbye and disappears completely. Out in the jungle, Ta and Cha-Ka share a bowl of food; when Ta snatches it away, the crowned little Paku boldly demands its return.

When Dad and Will return from their mapping expedition, Holly brags to her family about telling off the Zarn. Dad voices his wish that she should never have done so, and while she agrees, Holly notes that Zarn isn't so bad after all. Will asks his sister about Cha-Ka winning a fight with Ta, so Holly explains while it was partly Zarn's doing, she takes credit for teaching Cha-Ka to fight. She goes on to brag that she taught the little Paku that "the bigger they are, the harder they fall", but Cha-Ka then walks into the cave, his laurel crown all mangled. Dad comments that Cha-Ka's new leader status didn't last so long, and when Will teases his sister with "the bigger they are, the harder they hit", she throws Cha-Ka's crown at her brother, knocking him over.