A young policemen witnesses a bank robbery which will become his first case. To catch the thieves he will infiltrate himself as one of the gang members. At first it works, but it won't be so easy afterwards.
| Actor | Role |
|---|---|
 José SuárezFernando Olmos Sánchez | Fernando Olmos Sánchez |
 Manuel GasInspector Basilio Lérida | Inspector Basilio Lérida |
| SSoledad LenceCelia Albéniz | Celia Albéniz |
 Alfonso EstelaÓscar Román | Óscar Román |
| BBarta BarriMario | Mario |
| PPedro Córdoba de CórdobaEduardo Hernández | Eduardo Hernández |
| FFernando VallejoTaxista | Taxista |
| AAntonio S. AmayaEduardo | Eduardo |
 José Manuel PinillosLíder banda en primer atraco | Líder banda en primer atraco |
| TTomy CastelsMiembro de la banda | Miembro de la banda |
 Carlos RondaCorreo | Correo |
| MMatías FerretCajero del banco | Cajero del banco |
 José SolerComisario jefe | Comisario jefe |
 Maruchi FresnoIsabel - esposa del Inspector Basilio | Isabel - esposa del Inspector Basilio |
 Isabel de CastroNot listed | Not listed |
 Carlos OteroAlfredo | Alfredo |
 Mercedes MozartJulia del Campo | Julia del Campo |
| AAlfonso SantigosaNarrador (uncredited) | Narrador (uncredited) |