"Poppy" Many of the classic Hollywood comedians honed their comedy routines on the stage, and WC Fields was no different. He also had a career as an actor on the stage, appearing in the original production of the musical "Poppy." It was later turned into a comedy vehicle for Fields, minus most of the music. The connection between Fields and the stage gets even stronger if you remember that the comedian often parodied old-fashioned stage productions in movies like "The Fatal Glass of Beer" and "The Old Fashioned Way."
"Arsenic and Old Lace" Frank Capra's screwball thriller is so perfect it might be hard to imagine it coming from another source, but "Arsenic and Old Lace" is actually a very popular play that continues to be performed today. The story of a drama critic who learns his aunts are serial killers is hilarious and creepy, but the original stage production improves on the movie in one important way: The menacing Brewster, who is said by everyone to resemble Boris Karloff was actually played by Boris Karloff. If you ever get a time machine, consider traveling back to see one of those famous performances, never captured on film.
"Rope" Many directors "open up" the story when shooting a movie based on a play, adding scenes of characters going to the grocery store, getting their hair done, etc. Not Alfred Hitchcock, who shot this thriller about two college students who decide to murder their mutual friend, stuff him in a chest and serve drinks to his family and friends off of it at a party in close to "real time." He also wanted to simulate the effect of it all being in one continuous shot, although film technology at the time only allowed him to shoot in 10-minute takes at a time.
"A Streetcar Named Desire" The original play by Tennesee Williams was famous for its raw depiction of subjects like rape, homosexuality, suicide and more. This had to be cleaned up a little for the movie, but you wouldn't know it to watch Marlon Brando's famous performance as Stanley Kowalski. Brando changed movies forever with his unprecedentedly real and emotionally bracing performance, and the surrounding movie ain't bad neither.
"The Seven Year Itch" Here's another example of a play being altered before making it to the big screen. In the original play, a husband suffering from "the seven year itch" (that sudden urge to cheat on one's spouse after seven years of marriage) actually does the deed. Whereas in the movie, even when tempted by none other than Marilyn Monroe, he merely almost does it. The movie is still a hilarious classic, though.
Rabbit Hole," a story about a married couple who lose their young son in a car accident. It's just as bracing and emotionally brutal as the play, plus shots of people driving! If you like scenes of people not watching where they're going while driving, this movie's got at least two sequences that are just for you. Can't do that on the stage, nossir.