Reaction of 2-(4-chloro-3,3,7-trimethyl-2,3-dihydro-1H-indol-2-yl-idene)propane-dial with hydroxyl-amine gives the title compound, C(14)H(14)ClN(3)O, in which the ring N atom is essentially planar [sum of angles around the ring N atom = 361°], indicating conjugation with the 2-cyano-acryl-amide unit. The orientation of the acetamide group arises from intra-molecular hydrogen bonding between the indole N-H and carbonyl groups. In the crystal, inversion-related acetamide groups form N-H⋯O hydrogen-bonded dimers in graph-set R(2) (2)(8) motifs, whilst dimers are also formed by pairs of amine-nitrile N-H⋯N hydrogen bonds in R(2) (2)(12) motifs. These inter-actions together generate ribbons that propagate along the b-axis direction.