Lucille Ball - first early role - The Three Stooges 1934

#4 "Three Little Pigskins" - Released December 8, 1934
This was her first credited role though she had been in bit parts and as an extra in roughly 16 credits(per IMDB) spanning 1933 and 1934.
Ball's career began in 1929 when she landed work as a model. Shortly thereafter, she began her performing career on Broadway using the stage name Diane (or Dianne) Belmont. She later appeared in films in the 1930s and 1940s as a contract player for RKO Radio Pictures, being cast as a chorus girl or in similar roles, with lead roles in B-pictures and supporting roles in A-pictures. During this time, she met Cuban bandleader Desi Arnaz, and they eloped in November 1940. In the 1950s, Ball ventured into television, where she and Arnaz created the sitcom I Love Lucy. She gave birth to their first child, Lucie, in 1951,[6] followed by Desi Arnaz Jr. in 1953.[7] They divorced in March 1960, and she married comedian Gary Morton in 1961.[8]

Ball produced[9] and starred in the Broadway musical Wildcat from 1960 to 1961. In 1962, she became the first woman to run a major television studio, Desilu Productions, which produced many popular television series, including Mission: Impossible and Star Trek.[10] After Wildcat, she reunited with I Love Lucy co-star Vivian Vance for The Lucy Show, which Vance left in 1965. The show continued, with Ball's longtime friend and series regular Gale Gordon, until 1968. Ball immediately began appearing in a new series, Here's Lucy, with Gordon, frequent show guest Mary Jane Croft, and Lucie and Desi Jr.; this program ran until 1974.

Ball did not retire from acting completely, and in 1985 she took on a dramatic role in the television film Stone Pillow. The next year she starred in Life with Lucy, which, unlike her other sitcoms, was not well-received; it was canceled after three months. She did not appear in film or television roles for the rest of her career and died in 1989 from an abdominal aortic aneurysm and arteriosclerotic heart disease at the age of 77.