The object of the present invention is a ready-to-use agent for coloring keratin fibers containing (i) at least one heterocyclic hydrazone derivative of formula (I), (ii) at least one aromatic enamine of formula (IIa) or an acid addition compound thereof (IIb) and (iii) at least one oxidant, a multicomponent kit and a method for coloring keratin fibers by use of said agent ##STR00001##