The title compound, C(15)H(11)FN(4)OS, crystallizes with three independent mol-ecules (A, B and C) in the asymmetric unit. The dihedral angles between the nine-membered 5-fluoro-indolin-2-one ring system and the benzene ring are 22.14 (11), 12.56 (11) and 3.70 (11)° in mol-ecules A, B and C, respectively. In all three mol-ecules, intra-molecular cyclic N-H⋯O and C-H⋯S hydrogen-bonding inter-actions [graph set S(6)] are present in the N-N-C-N chain between the ring systems. In the crystal, the A mol-ecules form centrosymmetric cyclic dimers through inter-molecular N-H⋯O hydrogen bonds, which are linked into a supramolecular chain along [100] via C-H⋯F interactions; each type of hydrogen bond has graph set graph set R(2) (2)(8). A similar chain stabilised by similar interactions and also along [100] but, comprising alternating molecules of B and C is found. The latter chains are connected via C-H⋯S interactions, forming a layer with a zigzag topology parallel to (001).