The story is based on a vision Allen had during the full moon of Easter 1966, in which he claims he could see his future laid out before him.
The mythology is hinted at through all of Gong's earlier albums but is not the central theme until the "Radio Gnome Trilogy" (1973-1974).
The story begins on the album Flying Teapot (1973), when a pig-farming egyptologist called Mista T Being is sold a "magick ear ring" by an "antique teapot street vendor & tea label collector" called Fred the Fish. The ear ring is capable of receiving messages from the Planet Gong via a pirate radio station called Radio Gnome Invisible. Being and Fish head off to the hymnalayas of tibet (sic), where they meet (in a cave) the "great beer yogi" Banana Ananda. Ananda tends to chant "Banana Nirvana Manana" a lot and get drunk on Fosters Australian Lager.
This latter development mirrors the real-life experience of band-members Daevid Allen and Gilli Smyth, who met their saxophonist, Didier Malherbe in a cave in Majorca.
Meanwhile, the mythology's central character, Zero the Hero, is going about his everyday life when he suddenly has a vision in Charing Cross Road. He is compelled to seek after heroes and starts worshipping the Cock Pot Pixie, one of a number of Pot Head Pixies from the Planet Gong. These pixies are green with propellers on their heads, and they fly around in tea-pots.
Zero is soon distracted by a cat, which he offers his fish and chips to. The cat is actually the Good Witch Yoni, who gives Zero a potion.
This concludes the first album of the Radio Gnome Trilogy. The second album (Angel's Egg, 1973) begins with Zero falling to sleep under the influences of the potion, and finding himself floating through space. After accidentally scaring a space-pilot called Captain Capricorn, Zero locates the Planet Gong, and spends some time with a prostitute who introduces him to the moon-goddess Selene.
Zero's (drug-induced) trip to the Planet Gong continues, and the Pot Head Pixies explain to him how their flying tea-pots fly (a system known as Glidding). He is then taken to the One Invisible Temple of Gong.
Inside the temple, Zero is shown the Angel's Egg: the physical embodiment of the 32 Octave Doctors (descendants of the Great God Cell). The Angel's Egg is the magic-eye mandala that features on much of the band's sleeve-art. It is also a sort of recycling plant for Pot Head Pixies.
A grand plan is revealed to Zero: there will be a Great Melting Feast of Freeks which Zero must organise on Earth. When everyone is enjoying what to all intents and purposes will be a huge global concert, the Switch Doctor (the Earth's resident Octave Doctor, who lives near Banana Ananda's cave, in a "potheadquarters" called the Invisible Opera Company of Tibet (C.O.I.T.), and transmits all the details to the Gong Band via Bananamoon Observatory) will turn everybody's third eye on, ushering in a New Age on Earth.
In the third installment (You, 1974), Zero must first return from his trip. He asks Hiram the Master Builder how to structure his vision and build his own Invisible Temple. Having done this, Zero establishes that he must organise the Great Melting Feast of Freeks on the Isle of Everywhere (Bali).
The event is going well, and the Switch Doctor switches on everyones' third eyes except for Zero's. For Zero is out the back, indulging in Earthly pleasures, or Fruitcake (in the manner of Banana Ananda).
Zero has missed out on the whole third eye revelation thing, and is forced to continue his existence spinning around on the wheel of births and deaths, and slowly converging on the Angels Egg in a way which, to a certain extent, resembles Buddhist reincarnation.
In episode four (Shapeshifter, 1992), Zero meets an urban shaman who agrees to take Zero to the next level of awareness on the proviso that Zero spends nine months on an aeroplane, travelling where he wants but not using money or eating anything other than airline food. Zero eventually dies in Australia under mysterious circumstances.
The last installment (Zero to Infinity, 2000) sees Zero's spirit enjoying a body-free and virtual existence. During the course of this he becomes an android spheroid Zeroid. With the help of a strange animal called a gongalope, he learns that all the wisdom of the world exists within him, and practices Lafta yoga and tea-making. At the end he becomes one with an Invisible Temple, and has lots of fun.
As can be seen, the mythology is not universally serious, and great amounts of it pertain in some way to the production and consumption of tea.
The characters of the story are often based on / used as pseudonyms for band members, eg: Mister T Being = Mike Howlett, Good Witch Yoni = Gilli Smyth.