Pedro (Alberto Closas) and Julian (Rafael Alonso), two friends entomologists are in love the same woman, Adela (Conchita Montes), who decides to marry Peter. Julian attends the marriage, but acts against women as her own husband. The passion that unites the two friends, entomology, leads them to conclude a treaty. The woman, however, is not comfortable with the life she has lived and want to abandon them. Discovered that she suffers from the disease, makes men willing to please her in everything, without her knowing the reason for his change of attitude.