I have had my hair dyed blue (deliberately) and I love it. As it slowly washes out, it's a bit more teal - which I also love - but I've just found some of those hot shots when I was cleaning up. If I put that purple toner in, will it bring the blue back?
For background, my hair has been home dyed for years and I've had bleached streaks put in and crazy colour on top (if that makes a difference) so it's now a bluey/black colour with blue streaks through it.