unless there's a totally black & silent film*, I don't think anything's gonna top that for "nothing really happening"
* Surely some "artist" MUST have done this brrrriliant idea - Warhol, possibly?
The closest anyone's come to that is Guy Debord of "Society Of The Spectacle" and Situationism fame - his first feature, Howls For Sade, is described thus:
Howls for Sade, a feature-length film created in June 1952, contains no images whatsoever. The soundtrack is accompanied by a completely blank white screen during the spoken dialogues. These dialogues, which altogether total no more than twenty minutes, are broken up into short fragments amid passages of total silence totaling one hour (the final portion of the film consisting of an uninterrupted 24-minute period of silence). During the silences the screen, and thus the theater, remains totally dark.
Source:
Technical Notes on Guy Debord’s First Three FilmsThere was also a similar film made by one of Debord's associates, Gil Wolman, called "The Anticoncept". It differed in that instead of alternating black and white screens there was a big circle taking up most of the frame - which was obtained from some sort of common test footage used by film labs, if I remember rightly - which blinked off and back on for randomly chosen periods of time. For double wankiness points, he demanded it should be projected onto a weather balloon instead of a screen.
Amusingly, there was a cinema owner in Paris during this time who decided to take the piss out of Debord and his friends by advertising a fake film called "Sadistic Skeleton". It would have simply consisted of turning off the auditorium lights for 15 minutes. I think this guy also came up with a fake bio and stuff to advertise it. When Debord and the others caught wind of it, they went over to his cinema and basically bullied him into not "showing" it. I believe they wouldn't let him leave his office until the advertised time had passed. A key component of Situationism was the complete lack of any sense of humour.
Absolutely no recollection of any actual "plot" - just a lot of lovely blue.
I've never seen Blue, but I understand the film's actual content exists as some sort of abstract monologue (plus music) about Jarman's impending death from AIDS. Apparently he was losing his vision as a result of the disease and suffered frequent interrupting flashes of blue light, and so chose to use a pure blue screen to give people some kind of idea what he was going through.