I would go with that, too. I once dyed my hair dark brown and it went bottle black but anti dandruff shampoo did the trick in about five washes. I left it on for a bit between rinses, too, although I don't know if it made any difference. I also had some mega dark dye stripped at the hairdressers one time. It was really expensive and very painful but ended up a really lovely mid brown once they had applied the corrective shade over the top. The hairdresser told me that to do this latter process you must have dyed your hair the offending shade not more than 4 days ago as it makes the process much harder to reverse otherwise. Do let us know what happens x