While studying in Cluj-Napoca, the members started out as the 5-piece rock band Revers. In 2006, after having suffered multiple changes in the lineup, Grimus released a demo album. Their song Solitude is declared Song of the Year 2006 by City FM Radio. By 2007 the band received invitations to play at most music festivals in Romania.
In October 2007, Grimus won the National Finals of the Global Battle of the Bands and represented Romania in the World Finals.