Durante una función circense se produce un corte de luz. Al poco tiempo se descubre un asesinato, pero la orden es que la función debe continuar y se decide contratar a un detective para resolver el crimen.

It tells the story of an almost perfect crime that happened in one of the most important circuses in the country, the Tihany Circus. Several are the suspects that will come to light, but only one is responsible for the murder of the important businessman. Only an old commissioner (Tincho Zabala) will be able to discover the real culprit.