2-(4-Chloro-phen-yl)-4-[1-(4-chloro-phen-yl)-3-methyl-1H-pyrazol-5-yl]-5-methyl-1H-pyrazol-3(2H)-one.

The title compound, C(20)H(16)Cl(2)N(4)O, has two mol-ecules in the asymmetric unit. The two five-membered rings form a dihedral angle of 54.2 (3)° in one mol-ecule and 56.8 (3)° in the other independent mol-ecule. The amino group of the dihydro-pyrazolone unit of one mol-ecule acts as a hydrogen-bond donor to the carbonyl group of the dihydro-pyrazolone system of the other mol-ecule. The resulting N-H⋯O hydrogen bonds generate a chain running along the c axis. The crystal selected was a pseudo-merohedral twin with a 44.9 (3)% twin component.