In the title mol-ecule, C(16)H(13)NO, the indoline-2-one ring system is nearly planar [maximum atomic deviation = 0.082 (2) Å] and is oriented at a dihedral angle of 66.60 (12)° with respect to the phenyl ring. In the crystal, inter-molecular N-H⋯O hydrogen bonds link the mol-ecules into supra-molecular dimers.