In the mol-ecule of the title compound, C(20)H(14)N(2)O, the tetra-hydro-benzo[h]quinoline fused-ring system is buckled owing to the ethyl-ene -CH(2)CH(2)- fragment, the benzene ring and the pyridine ring being twisted by 19.7 (1)°. The 4-substituted aromatic ring is bent away from the pyridine ring by 62.9 (1)° in order to avoid crowding the cyanide substituent. In the crystal, two mol-ecules are linked by a pair of N-H⋯O hydrogen bonds to form a centrosymmetric dimer.