In the title compound, C(23)H(15)Cl(2)NS, the quinoline system is almost planar [r.m.s. deviation = 0.013 (2) Å]. The phenyl group is disordered over two positions with site occupancies of 0.55 and 0.45, and is oriented in a nearly perpendicular configuration to the quinoline ring [the dihedral angles between the quinoline ring and the major and minor disordered components of the phenyl ring are 81.8 (2) and 71.6 (2)°, respectively]. The dihydro-thiene ring adopts an envelope conformation. The dihedral angle between the chloro-phenyl ring and the quinoline system is 79.32 (1)°. In the crystal weak C-H⋯π inter-actions occur.