Fantasies, despite their constant presence in the human being, are a phenomenon which has a scarce interest in academic psychology (Kinsey y cols, 1948; 1953). Unlike sexual fantasies, where there are systematized studies from the 1940s, in relation to latent aggressiveness there is an important vacuum.

This study will try to throw evidences about the relation between different types of personality and the level of sadism and/or latent aggressiveness that prevails in each one of them, as well as the modus operandi that can be attributed to them. It also aims at check the evolution of the latent aggressiveness in relation to age.

Have been applied in the evaluation of the sadistic fantasies and aggressiveness the test MCMI (Millon, 1983), the test MACI and the Questionnaire of Sadism and Criminality (CSyC, 2013) which allows to predict certain criminal behaviors as well as know their modus operandi if they are carried out. The sample was formed by a group of adolescents aged between 13 and 18 years old and another group of adults from 40.

Latent aggressiveness levels seem to point a normal curve, being established the maximum peak in adolescence. Further, the qualitative study reflects relations between certain psychopathological profiles of personality and particular modus operandi.

The results of this study show the evolution of the levels of sadistic fantasies according to the age and the role that personality has in different criminal acts.