Greek director Costa-Gavras was unknown to me. He adapted Vassilis Vassilikos's novel of the same name with help from Jorge Semprún and Ben Barzman. It rates highly at IMDB on the paranoid/political thriller scoreboards, and indeed in general. Somewhat timely I guess, or perhaps it is always timely.
Yves Montand leads, at least for the setup, as a leftist politician who is in town to deliver a speech and rile up the masses. (Perhaps this is how George McGovern presented.) The local powers-that-be want to plausibly-deniably obstruct the gathering and just maybe put a stop to this socialist nonsense. But some go further than that, and then a magistrate ("Le juge d'instruction", an enjoyably ice-cold and chic Jean-Louis Trintignant) drives the whole show off a cliff.
It is incredibly well made and entirely engrossing. We're shown how everything goes down with scenes that are fluently sliced up in ways that exhibit the internal states and histories of the characters while leaving us solidly anchored in time and perspective. (Lone Star (1996) tried for a similar effect but was nowhere as ambitious.) The cast is solid, the pacing excellent, the telling well-humoured. It doubles as a post-war time capsule for Algiers. There's some good work on the soundtrack (by Mikis Theodorakis), especially in the scene where a bloke is cheating at pinball.
I was a bit mystified why this Greek director made this actual Greek story (from 1963) in French with French actors (excepting Irene Papas who mostly facially emotes) in Algeria. It got the Best Foreign Language Film Oscar for 1970 (submitted by Algeria!). Françoise Bonnot also deservedly won for Best Film Editing. I see that Costa-Gavras and Montand established a partnership similar to that of Melville and Delon (Le Samouraï (1967), etc.) and now have a new vein to mine.
Roger Ebert at the time: four stars, universal, Chicago and Sài Gòn. Armond White in 2009: it's not about the ideology... I'm not sure I can buy that. IMDB trivia: "The three-wheeled delivery vehicle that is referred to as 'kamikaze' is a 1965 Innocenti Lambretta Lambro 450."