In the title compound, C23H17FN2, the indole ring systems are oriented orthogonally, as indicated by the dihedral angle between them of 88.49 (5)°. The fluorophenyl ring is nearly perpendicular to one of the indole ring systems [dihedral angle = 85.31 (16)°] and twisted by 63.6 (6)° from the other. In the crystal, N—H...π, C—H...π and C—H...F interactions occur, forming a three-dimensional network.