The title compound, C17H14N2S, crystallizes in a triclinic unit cell, with two crystallographically independent molecules in the asymmetric unit. The two independent molecules pack in the same sense and form segregated layers along the c axis. The crystal is light-stable and no dimers are formed under irradiation. The intermolecular distances between the potential reactive centers (the C-3 and C-5 ring positions) are 4.093 (4) and 5.643 (4) Angstrom for molecule A, and 4.081 (4) and 5.614 (4) Angstrom for molecule B.