Desilu Productions was a company jointly owned by American actors Lucille Ball and Desi Arnaz. It was home to such television series as Star Trek, The Andy Griffith Show, Mission: Impossible!, The Untouchables, Mannix, The Mothers-in-Law, The Lucy Show, Here's Lucy, and of course, I Love Lucy.

Desilu's first studio was on Cahuenga Boulevard in Hollywood, at the site of what is now the Ren-Mar rental studio; the first episodes of I Love Lucy were filmed there. In 1956, the company bought the nearby RKO lot, and moved its facilities there.

Much of the studio's early success can be traced to Arnaz' unusual business style in his role as producer of I Love Lucy. For example, lacking formal business training, Arnaz knew nothing of amortization, and often included all the costs incurred by the production into the first episode of a season, rather than spreading them across the projected number of episodes in the year. As a result, by the end of the season, episodes would be nearly entirely paid for, and would come in at preposterously low figures. In addition, Arnaz took the unprecedented step of buying the episodes of I Love Lucy for an astoundingly low cost from CBS, realizing, as the network did not, the potential of the rerun.

The studio's initial attempt to become involved in film production was Forever Darling, Arnaz and Ball's follow-up to their highly successful The Long, Long Trailer, but it failed at the box office, and most subsequent attempts to bring projects to the big screen were aborted, until Yours, Mine, and Ours (with Ball and Henry Fonda) in 1968.

Another Desilu loss was Carol Burnett, who declined to star in a sitcom for the studio in favor of a weekly variety show that ultimately lasted eleven seasons. (Burnett and Ball, however, remained close friends.) Pilots for a comedy with Carol Channing and an adventure series with Rory Calhoun were shot but never sold. Arnaz was determined to create a law drama entitled Without Consent, with Spencer Tracy as a defense attorney, but after several attempts at developing a suitable script failed, the project was scrubbed.

After Arnaz and Ball's divorce in 1960, Lucy bought Desi's stake, leaving her in full control of the company. This made Ball the first woman head of a major Hollywood studio. Later, in 1967, the company was sold to Gulf+Western, which merged it with its other production company (and Desilu's next-door neighbor) Paramount Pictures. Desilu's holdings are currently owned by media conglomerate Viacom.

The studio was named after Arnaz and Ball's ranch.

In the Simpsons universe Krusty the Clown owns the eponymous "Krustylu Studios", a reference to Desilu.

Reference

Desilu: The Story of Lucille Ball and Desi Arnaz, by Coyne Steven Sanders & Tom Gilbert, William Morrow, 1993