Answer
Jansen was brought in as a replacement for Anette Olzon in 2012, who had been the lead singer of the Finnish symphonic metal band Nightwish since 2007. Olzon's departure from the band was due to creative differences and conflicts within the group. Jansen, a Dutch soprano and former member of the band After Forever, joined Nightwish shortly after Olzon's exit and has been the band's lead singer ever since.