Question: A 1966 American science fiction drama film directed by John Frankenheimer and starring an American actor, generally known for his turns as a leading man during which era's?

Context paragraphs:
All Fall Down (film): All Fall Down is a 1962 American drama film, adapted from the novel "All Fall Down" (1960) by James Leo Herlihy, the author of "Midnight Cowboy" (1965).  It was directed by John Frankenheimer and produced by John Houseman.  The screenplay was adapted from the novel by playwright William Inge and the film starred Eva Marie Saint and Warren Beatty.  Upon its release, the film was a minor box-office hit.  Together with her performance in Frankenheimer's "The Manchurian Candidate" (1962), Angela Lansbury (who played a destructively manipulative mother in both films) won the year's National Board of Review Award for Best Supporting Actress.  The film was entered in the 1962 Cannes Film Festival.

Impossible Object: Impossible Object, later released as Story of a Love Story, is a 1973 drama film starring Alan Bates and Dominique Sanda.  It was directed by John Frankenheimer with a screenplay by Nicholas Mosley based on his own novel.  It was screened at the 1973 Cannes Film Festival, but was not entered into the main competition.  Mosley wrote the screenplay at the behest of director Joseph Losey, whose film "Accident" was based on an earlier Mosley novel.  Dirk Bogarde and Catherine Deneuve had been attached to the film.  However, Losey had difficulty financing the film and later fell out with Mosley over "The Assassination of Trotsky."  Frankenheimer, looking to make an independent film, took over the project.

Seconds (1966 film): Seconds is a 1966 American science fiction drama film directed by John Frankenheimer and starring Rock Hudson.  The screenplay by Lewis John Carlino was based on "Seconds, a novel" by David Ely.  The film was entered into the 1966 Cannes Film Festival and released by Paramount Pictures.  The cinematography by James Wong Howe was nominated for an Academy Award.

John Gilbert (actor): John Gilbert (born John Cecil Pringle; July 10, 1899 – January 9, 1936) was an American actor, screenwriter and director.  He rose to fame during the silent film era and became a popular leading man known as "The Great Lover".  At the height of his career, Gilbert rivaled Rudolph Valentino, another silent film era leading man, as a box office draw.

Prophecy (film): Prophecy is a 1979 American science fiction horror film directed by John Frankenheimer and written by David Seltzer.  It stars Robert Foxworth, Talia Shire and Armand Assante.  Set in the Androscoggin River, the film follows an environmental agent and his wife filing a report on a paper mill in the river, not knowing that the paper mill's waste made a local bear mutate, having the bear turn rampant in the wilderness.

Grand Prix (1966 film): Grand Prix is a 1966 American drama film about motorsports featuring an international ensemble cast.  The picture was directed by John Frankenheimer with music by Maurice Jarre and stars James Garner, Eva Marie Saint, Yves Montand, Brian Bedford, Jessica Walter and Antonio Sabàto.  Toshiro Mifune has a supporting role as a race team owner, inspired by Soichiro Honda.  The picture was photographed in Super Panavision 70 by Lionel Lindon, and presented in 70 mm Cinerama in premiere engagements.  Its unique racing cinematography – in part credited to Saul Bass – is one of the main draws of the film.

Rock Hudson: Rock Hudson (born Roy Harold Scherer Jr.; November 17, 1925October 2, 1985) was an American actor, generally known for his turns as a leading man during the 1950s and 1960s.

The Island of Dr. Moreau (1996 film): The Island of Dr. Moreau is a 1996 American science fiction horror film, the third major film adaptation of the 1896 novel "The Island of Doctor Moreau" by H. G. Wells.  The film was directed by John Frankenheimer (who was brought in half a week after shooting started) and stars Marlon Brando, Val Kilmer, David Thewlis and Fairuza Balk.  The screenplay is credited to the original director Richard Stanley and Ron Hutchinson.

Ray Milland filmography: This is a filmography of Welsh actor Ray Milland, containing his work in theatrically released motion pictures as well as his extensive television credits.  Milland began his film career in United Kingdom in 1929 after serving three years as a guardsman in the Royal Household Cavalry, based in London.  After appearing in several British films, he came to the United States in 1930 where he spent several years playing small and supporting roles.  Eventually, in 1934, he became a contract player at Paramount Pictures where he established himself as a popular star.  Milland remained with Paramount for the next 21 years.  During his time with the studio, he developed his persona as a debonair leading man, mainly in drawing-room comedies but also occasionally in adventure and mystery films.  In 1945, Milland won the Academy Award for Best Actor for his portrayal of an alcoholic writer in "The Lost Weekend".  From there he continued as a leading man well into the 1960s, appearing in several film noirs and occasionally cast as a villain.  In 1953, Milland began working in television as both an actor and director.  He alternated between the mediums of film and television for the remainder of his career.  During the 1960s and 1970s, Milland frequently worked in science fiction and horror films.  He also directed himself in four films.

The Young Savages: The Young Savages is a 1961 crime drama film directed by John Frankenheimer, starring Burt Lancaster, and written by Edward Anhalt from a novel by Evan Hunter.  The supporting cast includes Dina Merrill, Shelley Winters, and Edward Andrews, and "The Young Savages" was the first film featuring Telly Savalas, who plays a police detective, foreshadowing his later role as "Kojak".  Often categorized as a "thinking man's movie", it has received mixed reviews.

Supporting paragraphs: Seconds (1966 film) Rock Hudson
Answer: 1950s and 1960s