When I stopped at a salon supply store to get blue hair dye, the woman who owned the place managed to express her consternation in her Russian-accented English. As I left she said, "You stop back, want to see!"
Stage one, which was lifting the color out to be as close to white as possible resulted in a shade which I can only call "Accident at the Barbie Factory Blonde" - a sort of Dr. Seuss-like combination of pinks, oranges, whites and yellows.
The final result is not quite as vivid as I had hoped - the remaining red from the purple-incident left some peculiar streeks of green-purple, but ... well, you can judge for yourself.
It will probably wash out fairly quickly, and once it does I suppose I'll go back to a sane brown. But for now ...