The indolyl -NH group of the title Schiff base, C(19)H(19)N(3)O(2), forms a hydrogen bond to the -OH group of an inversion-related mol-ecule, resulting in a hydrogen-bonded dimer; adjacent dimers are further linked through an inter-dimer N-H⋯O hydrogen bond involving the -C(=O)-NH-N=fragment to form a linear ribbon that runs along the a axis.