The Set-Up (1949) is a terrific Noir thriller about a boxer who is supposed to throw a fight at behest of gangsters, and watching his decision play out in real time.
12 Angry Men (1957) puts you inside a closed room as the jury deliberates on a murder case, shown in real time until a unanimous verdict is achieved.
Dog Day Afternoon (1975) dramatizes an actual botched bank robbery and follows what happens inside and outside the bank in real time.
Rope (1948) has Hitchcock play with the real time convention with as few cuts as he could manage given the technology of the day, as we watch two Leopold & Loeb type murderers hold a dinner party with the corpse in the room and see if their professor can figure it out and, if so, if he is sympathetic towards their demented games.
United 93 (2006) follows in real time the events of that ill-fated flight on the morning of September 11, 2001.
My Dinner with Andre (1981) is a real time conversation between Andre Gregory and Wally Shawn as they discuss art, politics, and the nature of reality.
Russian Ark (2002) with the advent of digital technology somebody was finally able to do what Hitchcock couldn't and make an entire feature length film in one single take. This one has a camera travel through Russia's Hermitage Museum with characters and sets moving into and out of frame showing basically the entire history of St. Petersburg.
Run Lola Run (1998) takes place in real time, although the narrative is rebooted twice so you get the first twenty minutes of the story three different times before it concludes. Clever, energetic, and fun!
Cléo from 5 to 7 (1962) may be my favorite of them all, Agnès Varda's examination of a young woman spending two hours pondering life and death as she waits for the results of a medical test.
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