The poor trio of best friends Do, Re and Mi live in a simple treehouse in the forest, where they work together collecting, cutting and selling firewood at the local marketplace. One night they hear a voice calling for help in the forest. Although they are scared that it is a spirit trying to trick them, they follow the voice and discover that it is coming from a bamboo tree. The bamboo tree is wounded, and asks them to pull out the arrow that is stuck in it. They comply, and the bamboo transforms into a fairy princess, who explains that she is the Tuan Puteri Buluh Betong (Giant Bamboo Princess). When Do asks her whether she is related to Anak Buloh Betong (a character of S. Kadarisman's film Anak Buloh Betong), she explains that he is her father. She thanks them and gives them each a magical item. Do receives a magic carpet that can fly, Re receives a telescope that can see anything the viewer asks of it, and Mi receives a harmonica that can give them any wishes they want.
The trio decide to use their items to find their fortune. Re uses the telescope to find that the Sultan of their kingdom is looking for brave men to become his Admirals. The trio attend the competition that is being held to find the bravest and strongest men. Mi uses his harmonica to give the trio superhuman strength, and they win the competition easily. I, The Sultan, impressed by their feats, makes them his Admirals.
As part of an assignment, the Admirals are sent to an ally neighbouring kingdom, Pasir Dua Butir (lit. 2 Grains of Sand) that is under attack by Fasola, a former Minister of Defense turned traitor after his proposal to the sultan's princess, Princess Puncak Mahligai was rejected. In an act of retaliation, he and his army sack the entire kingdom, rape young girls, butcher loyal civilians and going as far as raze the palace to ground, an act that is considered brainless. He also hold the princess captive in his hiding place. After seeing his princess' distress through Re's binocular, the sultan then promises to marry his princess to anyone who slays Fasola. The excited Do, Re and Mi then sets out on their rescue missions.
They then defeated whole of Fasola's army, some of it by using Mi's wish-granting harmonica with comical result (make them dancing, for instance). They then confront Fasola. After being insulted by Do, in a fit of rage he defeats them single-handedly with little effort. He and Do then have a sword fight. When it seems that Do gets the upper hand by stabbing Fasola, it is revealed that Fasola is magically impervious to any attack. By using Re's binocular to seek Fasola's weakness, it is revealed that Fasola can only be killed by stabbing a sharp bamboo to his sole. Mi then uses his harmonica to provide them with a sharp bamboo. Seeing the sharp bamboo in Do's hand, Fasola is frightened and he even begs Do to spare his life but Do nonetheless kill him and thus ends the traitor's life.
They free the Princess, whom all three fall in love with. When Do, Re and Mi fight over her, the Princess declares that she will marry all three of them, which three of them agreed, although stunned at first. (The princess reason that if men are able to practice polygamy, why don't women as well?) Do, Re and Mi return to their sultan in triumph. The sultan, like the trio, also falls in love with the princess. When the sultan finds out their odd situations, he then remind them the tale of the legendary Malay Admiral, Hang Tuah who presents Tun Teja, the princess of Pahang to his sultan as sign of his undivided loyalty, despite Hang Tuah and Tun Teja deeply love each other. Then, why don't the Admirals Do, Re and Mi emulate him? The princess, impressed by the sultan's wisdom, agreed. The sultan then announce his wedding to the princess and the entire court give their full approval. Of course, the three Admirals disappointed but the sultan offers to reward them with three palace handmaidens as their handmaidens, whom the sultan claimed are very beautiful. However, it turns out the handmaidens are ugly, old hags. The sultan jokingly tells them the three Admirals are their future husbands! The handmaidens are thrilled and start chasing the Admirals, while the entire court laugh. The Admirals, don't wish to end up marrying old hags, flee with their magic carpets and sending them itchy all over their bodies with Mi's harmonica. Do, Re and Mi laugh at the helpless hags and then flies to an unknown destination.
According to the princess, Anak Buloh Betong, a demon child that is sired by an evil spirit and was conceived in a Dendrocalamus asper is her father. Anak Buloh Betong was found by the royal family when he is still an infant and is later adopted by them. The child grows up into an evil and unruly prince. When he realizes his true parentage after his outraged foster father, the sultan strikes him and then calls him a child of the forest demon due to his behaviour. He then departs to the bamboo clumps where he was born and met his demonic biological father, and gains his supernatural powers, making him invincible. However he can only be defeated and slain by Panglima Lintah, his sworn enemy. The prince then usurps his foster father's throne and rules with iron fists. At the end of the film, Panglima Lintah burns his bamboo clumps, the source of his powers and his only mean to heal himself, and later kills him.
At some point, it is possible that he sires the princess with an unknown partner, since Princess Buloh Betong confirms that the prince is her father when Do asks her whether she is somehow related to the Anak Buloh Betong, a character in S Kadarisman's movie, in which he is portrayed. The princess doesn't seem to be offended with Do's question, since Anak Buloh Betong is evil. It is unknown whether Anak Buloh Betong is aware that he has a daughter.
The princess then tell Do that she will return to the heavenly realm to heal her injury, meaning that at one point she moves there. It is unknown who imprisons her, and the reasons for it. A likely suspect is his her grandfather, the evil spirit who fathers Anak Buloh Betong. In the film, the evil spirit is able to turn his own son into a bamboo stalk, so it must be him that does the same to the princess and then imprisons her.P. Ramlee as DoA. R. Tompel as ReIbrahim Din as MiDayang Sulu as Tuan Puteri Buluh BetungHussein Abu Hassan as Pasola