In the crystal structure of the title compound, C(21)H(17)NO(3), the dibenzo-isoquinoline-dione unit has a planar structure, the maximum atomic deviation being 0.091 (3) Å. The crystal structure is stabilized by π-π stacking [centroid-centroid distance = 3.851 (2) Å] and inter-molecular N-H⋯O hydrogen bonding.