Studios hid actors' names on purpose
In the earliest years of film nobody in the cast was credited, and that was deliberate. The studios had worked out that an anonymous performer could not be poached and could not demand a rise, so audiences knew faces without names — the woman in the Biograph films was known simply as the Biograph Girl, and letters arrived at the studio asking who on earth she was.
In 1910 a rival producer signed her away, revealed that her name was Florence Lawrence, and staged a publicity stunt around her. It worked so completely that the entire economics of the business reversed within a few years. The studios had accidentally proved that audiences would pay to see a particular person, and the star system they had been trying to prevent turned out to be the most valuable thing they owned.
The most famous costume in cinema was assembled in an afternoon
Asked in 1914 to put on comedy makeup for a short, CHAPLIN went to the costume basket and grabbed items for contrast: trousers far too baggy, a jacket far too tight, enormous shoes, a small bowler, and a moustache trimmed down so it would not hide his expressions. He said the character arrived fully formed as he walked onto the set in it.
Within four years he was among the highest-paid people on earth and the Tramp was recognisable in countries that had never had a cinema. The lesson every studio drew was the wrong one — that a look could be manufactured — when what had actually happened was an improvisation by a performer who understood that the audience reads silhouettes before faces.
For thirty years the studio owned you
The star system the studios stumbled into was then locked down hard. From the 1920s an actor signed a seven-year contract that gave the studio control of nearly everything: which films you made, who you were loaned out to, what you were photographed doing, sometimes your name and your teeth. Refuse a part and you were suspended without pay — and the suspension was added to the end of the contract, so seven years could quietly become ten.
Olivia de Havilland took Warner Bros to court over exactly that in 1943 and won, twice, on appeal. Californian law was found to mean seven years and not seven years of work. The ruling is still called the De Havilland Law, it cost her most of three years of her career while it went through, and it is the single biggest reason the people in this grid work for themselves rather than for a company.
Nobody knows anything
That is the screenwriter William Goldman's summary of the whole industry: not one person can reliably tell in advance whether a film will work. Stars exist largely as an attempt to make an unpredictable business slightly less so — a recognisable name is the closest thing to a guarantee that anybody has found, and it is not much of one.
The grid holds several generations of that bet. BOGART, MONROE and BRANDO; NICHOLSON, PACINO and FREEMAN; STREEP, DENCH, ROBERTS and BLANCHETT; HANKS, WASHINGTON, HOPKINS, CRUISE, PITT, DEPP, SMITH, DiCAPRIO, HATHAWAY and LAWRENCE. HEPBURN is doing double duty for two unrelated and equally famous actors, Katharine and Audrey, which is one of the hazards of a grid built from surnames — and the classics page has more on the films themselves.