The title compound, C(21)H(21)N(3)O, was obtained by cyclo-condensation of 3-amino-5-methyl-[1,1'-biphen-yl]-2,4-di-car-bo-nitrile with cyclo-hexa-none. The six-membered 1,3-diaza ring assumes an envelope conformation [with the flap atom displaced by 0.511 (7) Å from the plane through the other ring atoms] and the cyclo-hexane ring displays a chair conformation. The dihedral angle between the aromatic rings is 42.61 (7)°.In the crystal, the mol-ecules form hydrogen-bonded bands along [011].