The great Italian directors Paolo and Vittorio Taviani film the staging of Julius Caesar with inmates of the Rebibbia Maximum-Security Prison in Rome; the result is not a straight documentary but an eccentric Shakespeare adaptation, a condensed version of the play assembled from months of rehearsal footage. Throughout, the Tavianis blur the line between fiction and nonfiction filmmaking, ingeniously shooting the prison so that it looks like a set and having the prisoners comment on the action in scripted asides that mimic Shakespearean prose. Ultimately the distinctions between drama and documentary seem less important than Shakespeare’s human insights, which the Tavianis render stirringly immediate. In Italian with subtitles.