I understand why Medium Cool has some historical significance in terms of filmmaking technique and such, but setting that aside and just assessing it as a movie, I’d say it’s no more than OK.
Set in Chicago in 1968 (the movie itself came out in 1969, so pretty much contemporaneous), Medium Cool is fiction, but it’s shot in kind of a docudrama way, with footage of actual events intermixed with its conventional movie scenes. It follows the activities of various parties in the city (including black activists, antiwar protesters, working class people from the country and the South who have moved to the big city seeking better opportunities, National Guard members training to respond to protests and riots, and more), mostly people from marginal groups whose perspectives are least often given an airing.
Insofar as there is a coherent plot, the glue holding these various elements together into a story is a TV crew—filming these people, interviewing them, arguing amongst themselves about them, having political and philosophical discussions about them and about the role of the media and television specifically in modern society, etc.
The film culminates with scenes from that year’s Democratic convention, where the police rioted and went on a rampage against protesters and anyone else who happened to get in their way, singling out the press in particular for their violent attention.
This structure enables Medium Cool to address various political issues of the day, especially those related to the mass media, with, for instance, the black activists lecturing a TV reporter about how the media ignores and implicitly devalues their claims for justice, and a conflict arising at the TV station when it is discovered that the station’s higher ups have been sharing the material they’ve gathered with law enforcement.
These and other issues raised are certainly interesting and worth thinking about, but it’s not as if Medium Cool goes into them in any deep way—certainly less than, say, a good quality documentary about that historical period would. And because it’s delving into these matters via fiction, there is a stilted, artificial quality to some of the dialogue.
Of the films I’ve written about previously, I suppose Medium Cool overlaps most with Punishment Park, a pseudo-documentary from 1971 about antiwar protesters and various leftists being rounded up, convicted of various crimes in kangaroo courts, and punished under a martial law regime. If anything, Punishment Park is even more awkward and didactic in much of its dialogue. On the other hand, Punishment Park reached me emotionally in a way that Medium Cool never did.