Best Investigation movies of 1971

Actors : Sean Connery, Jill St. John, Lana Wood, Charles Gray,
Directors : Guy Hamilton,

A diamond smuggling investigation leads James Bond to Las Vegas, where he uncovers an evil plot involving a rich business tycoon.

Actors : Arthur Hill, David Wayne, James Olson, Kate Reid,
Directors : Robert Wise,

A group of scientists investigate a deadly new alien virus before it can spread.

Actors : John Osborne, Ian Hendry, Britt Ekland, Michael Caine,
Directors : Mike Hodges,

When his brother dies under mysterious circumstances in a car accident, London gangster Jack Carter travels to Newcastle to investigate.

Actors : Roy Scheider, Jane Fonda, Charles Cioffi, Donald Sutherland,
Directors : Alan J. Pakula,

A small-town detective searching for a missing man has only one lead: a connection with a New York prostitute.

Actors : Christopher St. John, Moses Gunn, Richard Roundtree, Charles Cioffi,
Directors : Gordon Parks,

Cool black private eye John Shaft is hired by a crime lord to find and retrieve his kidnapped daughter.

Actors : Jack Weston, George Rose, Walter Matthau, Elaine May,
Directors : Elaine May,

Henry Graham lives the life of a playboy. When his lawyer tells him one day that his lifestyle has consumed all his funds, he needs an idea to avoid climbing down the social ladder. So he intends to marry a rich woman and - murder her.

Actors : Melvin Van Peebles, John Dullaghan, Simon Chuckster, Hubert Scales,
Directors : Melvin Van Peebles,

After saving a Black Panther from some racist cops, a black male prostitute goes on the run from "the man" with the help of the ghetto community and some disillusioned Hells Angels.

Actors : John Hurt, Judy Geeson, Pat Heywood, Richard Attenborough,
Directors : Richard Fleischer,

Based on the real-life case of the British serial killer John Christie, and what happened to his neighbors Tim and Beryl Evans.

Actors : Joanne Woodward, Jack Gilford, Lester Rawlins, George C. Scott,
Directors : Anthony Harvey,

In a Manhattan psychiatric hospital a man, convinced he is Sherlock Holmes, is treated by a female doctor who happens to be named Watson.

Actors : Telly Savalas, Angie Dickinson, Rock Hudson, John David Carson,
Directors : Roger Vadim,

California State Police Captain Sam Surcher investigates a string of teenage girl murders at Oceanfront High School.

Actors : Edwige Fenech, Manuel Gil, George Hilton, Conchita Airoldi,
Directors : Sergio Martino,

An ambassador's wife discovers that one of the men in her life - either her husband, an ex-lover or her current lover - may be a vicious serial killer.

Actors : Barbara McNair, Sheree North, Sidney Poitier, Gerald S. O'Loughlin,
Directors : Don Medford,

In San Francisco, Police Lieutenant Virgil Tibbs helps a group of idealistic vigilantes expose a drug ring controlled by powerful businessmen.

Actors : Charles Bateman, Strother Martin, L.Q. Jones, Ahna Capri,
Directors : Bernard McEveety,

A family is trapped in a desert town by a cult of senior-citizens who recruit the town's children to worship Satan.

Actors : Barbara Bouchet, Giancarlo Giannini, Claudine Auger, Rossella Falk,
Directors : Paolo Cavara,

Inspector Tellini investigates serial crimes where victims are paralyzed while having their bellies ripped open with a sharp knife, much in the same way tarantulas are killed by the black ...

Actors : Alberto de Mendoza, Anita Strindberg, George Hilton, Ida Galli,
Directors : Sergio Martino,

The Case of the Scorpion's Tail begins with the mysterious death of a millionaire and spirals into the murder of his suddenly rich wife, which draws the attention of a dogged investigator, who follows a trail of blood to the bitter end.

Actors : Albert Finney, Janice Rule, Frank Finlay, Billie Whitelaw,
Directors : Stephen Frears,

Nightclub comedian Eddie Ginley fulfills his Dashiell Hammett love by putting an ad in the paper as a private eye.

Actors : Christine Kaufmann, Jason Robards, Herbert Lom, Adolfo Celi,
Directors : Gordon Hessler,

Paris...at the turn of the century. Inspector Vidocq investigates a series of unexplained murders at a Grand Guignol-type theatre...where the players have suddenly become real-life victims. Based on the story by Edgar Allan Poe.

Actors : Alexander Knox, Sven-Bertil Taube, Patrick Allen, Barbara Parkins,
Directors : Geoffrey Reeve,

Following a triple professional hit a U.S. agent arrives in Amsterdam to investigate a heroin smuggling ring. He finds a city rife with drugs and a police force unable or unwilling to do ...

Actors : Silvia Monti, Wolfgang Preiss, Franco Nero, Ira von Fürstenberg,
Directors : Luigi Bazzoni,

An alcoholic journalist finds himself on the trail of a murderer after the police make him a suspect in their investigation.

Actors : Evert Anderson, Anja Schmidt, Thommy Berggren, Kelvin Malave,
Directors : Bo Widerberg,

About the life and death of the legendary Swedish/American agitator Joe Hill.