Volcano was one of four audio adventures released by Power Records around 1974, featuring the characters from the Planet of the Apes TV series. Unlike the other three, this story was not released as a stand-alone "Little LP" issue, but rather was held back for inclusion only on an LP compiling the four TV-based stories together.
The other, previously-released stories included on the album were:
Gorilla-chimp rivalry has reached a critical point when Zaius is visted by Dr Pandera, an expert in earthquakes and volcanic activity. She warns him that the Mount Praylox district is under urgent threat of disaster and should be evacuated immediately. Zaius reminds her that Praylox is a gorilla stronghold and they may not obey him. Meanwhile Urko and his next-in-command Captain Soma are plotting to depose Zaius and take over Central City. The three fugitives are travelling through Praylox and visit a human village there. A chimp sent by Zaius warns the people to flee Praylox but he is killed by Soma, who tells them it is only a trick by Zaius. When the earth starts to shake, Pete tells the humans they have to leave. He is recognised by Soma and is about to be arrested when Mount Praylox suddenly erupts and both the humans and the gorillas are forced to run for their lives. Galen tells Virdon and Burke that after this the gorillas will have to see the error of their ways and to trust Zaius.