In the title compound, C15H14N2O, the fused five- and six-membered ring system is essentially planar, the maximum deviation from the mean plane being 0.009 (1) Å. The benzimidazol-2(3H)-one residue is nearly perpendicular to the benzyl ring, forming a dihedral angle of 77.41 (6)°. In the crystal, inversion dimers are formed by pairs of N-H⋯O hydrogen bonds; these dimers are linked by weak C-H⋯O inter-actions into a two-dimensional array in the (102) plane.