In the title compound, C(21)H(17)N(3)O(4), pairs of mol-ecules form a planar[maximum deviation 0.0566 (9) Å] centrosymmetric imidazole dimer via two N-H⋯O hydrogen bonds. These dimeric units are linked by further N-H⋯O hydrogen bonds between the ester carbonyl group and the imidazolidine ring, formiing chains parallel to the c-axis direction. In addition, there are π-π stacking inter-actions between the planar imidazole pairs, with an inter-planar spacing of 3.301 (2) Å. There is a double bond with Z geometry connecting the imidazolidine and indole units.