"Helix the Cat" is a science fantasy short story by American writer Theodore Sturgeon.
The story was written in 1939 or 1940 and submitted to John W. Campbell, editor of Unknown and Astounding Science Fiction magazines.
The editor rejected it, as he felt it did not fit into either fantasy or science fiction categories.
Whilst experimenting with a new form of glass, he is trying to perfect, Pete is astonished to hear a disembodied voice from within the bottle he is working with.
But when Helix/Gregory start to take over Tronti's life, he decides he has no option but to kill the cat.