Her first film job was a bit part in a 1947 Betty Grable picture called "The Shocking Miss Pilgrim." But Monroe was cut from that movie, so she she didn't make her screen debut until later that year, when she appeared as a waitress in "Dangerous Years" (pictured).
Playing an uncredited lab technician in "Revenge of the Creature," the 1955 sequel to "Creature From the Black Lagoon," the future Dirty Harry began his 60-year (and counting) career with the line, "Doc, would you come here a minute?"
Belgium-born Hepburn played a stewardess in the 1948 Dutch film "Dutch in Seven Lessons." Six years after that screen debut, she would win an Oscar for Best Actress.
Actor and future salad dressing czar Newman hit it big with the 1954 epic "The Silver Chalice" after a few years of acting on Broadway. Years later, he would describe the project as "the worst motion picture produced during the 1950s."
Taylor was just nine when she made her screen debut in 1942's "There's One Born Every Minute."
Dean first appeared on television in a 1951 episode of "Family Theater," playing John the Apostle in a story that melded the biblical crucifixion with World War II. He would appear in only seven films (with significant parts in just three of them) during his five-year movie career.
The most nominated actor in Academy Award history first appeared on screen in 1977, alongside Jane Fonda in "Julia."
Streep: "I had two scenes in the movie. They cut one and they put the [lines] from the one that was cut into my mouth for the second scene. So it's like the worst debut, I think, anybody's ever made."
The King of Cool's career started inauspiciously as an extra in two carnival scenes of the 1953 low-budget indie "Girl on the Run." Seen here swinging a hammer, he would go on to become the highest paid actor in the world.
After working as a model in New York, Ball broke into Hollywood with small roles in four 1933 films. Though "The Bowery" was the first to be released, "Roman Scandals"—in which she played a slave—was the first movie she worked on.
A decade before he played Clyde to Faye Dunaway's Bonnie, Beatty received his first screen credit as the "First Card Player" in a 1957 installment of "Studio One in Hollywood" entitled "The Night America Trembled."
Bonnie, meanwhile, started her career with a bang. Dunaway appeared with Michael Caine and Jane Fonda in the Otto Preminger picture "Hurry Sundown" in 1967—the same year she starred in "Bonnie and Clyde."
Robert De Niro
The star of "Taxi Driver" first appeared on screen, surprisingly enough, in a 1965 French drama called "Three Rooms in Manhattan." De Niro, seen in the background of this shot, had already worked with Brian De Palma on "The Wedding Party" in 1963, but that film would not be released for another six years.
The international star got her start as an extra in this restaurant scene from the 1950 Italian film "Hearts at Sea." Which of the extras seen here is Loren? That's unconfirmed, but our money is on the woman seated on the right side of the frame.
In 1960, at 24 years old, Robert Redford got his start with appearances in eight television programs. The first was an episode of ABC's Western series "Maverick" (pictured). Some 55 years later, Redford's acting career is still going strong, with two films out this year and another coming in 2016.
After originating the part of Stanley Kowalski in "A Streetcar Named Desire" on Broadway in 1947, Brando had a substantial first film role, as a wheelchair-bound World War II lieutenant in 1950's "The Men." He would receive his first Oscar nomination less than two years later, for playing Stanley again in the screen adaptation of "Streetcar."
Keaton first hit the big screen in the 1970 comedy "Lovers and Other Strangers," a year after she appeared opposite Woody Allen for the first time in the stage run of "Play It Again, Sam."
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