In the title compound, C(20)H(26)N(2)OS, four non-H atoms of the thio-urea unit are approximately planar (r.m.s. deviation = 0.005 Å); the phenyl and benzene rings are twisted out of this plane by 28.55 (7) and 60.00 (7)°, respectively. An intra-molecular N-H⋯O hydrogen bond occurs. The hy-droxy group is hydrogen bonded to the double-bond S atom of an inversion-related mol-ecule, generating a hydrogen-bonded dimer in the crystal structure.