Best Investigation movies of 1970s

Actors : Luigi Pistilli, Gianni Agus, Annabella Incontrera, Franco Franchi,
Directors : Oscar Brazzi,

Two detectives are hired by an old countess to find out whether a villa she wants to turn into an orphanage is haunted. They find out that the noble-woman's relatives are involved : they do...

Actors : Frej Lindqvist, Per Myrberg, Agneta Ekmanner, Christina Schollin,
Directors : Vilgot Sjöman,

Psychological thriller where a religion teacher's wife is having an affair with the school principal. Guilt feelings in the situation leads to both attempted suicide and murder.

Actors : Eleni Erimou, Manos Katrakis, Yorgos Moutsios, Nikos Kourkoulos,
Directors : Nikos Foskolos,

A young investigator finds out that have led rather unjustly his old sweetheart in prison on charges of the murder of her husband. Decides to again investigate the case, with the help of an...

Actors : José Lewgoy, Gil Gomes, Marineide Vidal, Tião Ribas D'Avila,
Directors : Clery Cunha,

Story based on a true event. Shoe salesman arrives home and finds his wife and a young friend murdered. Crime reporter and insurance agent join forces to solve the mystery, taking a walk on the wild side of the city.

Actors : Elisabeta Jar, Draga Olteanu Matei, Octavian Cotescu, Silviu Stanculescu,
Directors : Maria Callas Dinescu,

A police officer is investigating the disappearance of a colleague's young boy. His key seems to be the "dark skinned" friend of the boy about whom nobody cares, including the police.