Update 27 Feb: the video has unfortunately been removed.
Althusser, an Intellectual Adventure – a film by Bruno Oliviero.
The entire film is available on Youtube. Thanks to Irina Culic for the link.
The interview with Althusser is in Italian, with French subtitles. Most of the film is in French. YouTube makes French subtitles available – but they are automatic and not at all reliable [updated]. Includes interviews with Etienne Balibar, Jacques Rancière, Pierre Macherey, Lucien Sève, etc.