The title compound, C(24)H(18)N(2), is the first structural example containing the 3,4-dihydro-benzo[b][1,6]naphthyridine fragment. It was synthesized from 2,4,6,8-tetra-phenyl-3,7-diaza-bicyclo-[3.3.1]nonan-9-one and was crystallized from a methanol-ethanol solution over two years as a racemate. The C=N double bond [1.2868 (15) Å] is bent significantly out of the plane of the aromatic bicyclic ring system [N-C-C-C = -157.63 (12)°] and out of the plane of the phenyl ring bonded at the 1-position [N-C-C-C = 41.15 (16)°].