Despite its lean and hungry look, the Taviani Brothers’ “Caesar Must Die” — winner of the Golden Bear last year in Berlin and opening Wednesday at Film Forum in New York — may be the most effectively gimmicked version of Shakespeare’s “Julius Caesar” in the 75 years since Orson Welles’s modern-dress, anti-fascist staging.

The movie begins with the production’s final scene. Having lost the battle against Caesar’s heirs, conspirator Brutus persuades a scary-looking pug-ugly to facilitate his suicide. The audience rises for a standing ovation, the cast (many lying “dead” on the stage) get to their feet to cheer in response and are then led back to their cells. Color stock is superseded by black-and-white.

Made on location in a Roman maximum-security prison, “Caesar Must Die” is an example of Pirandellian neo neo-realism, both a recording of an actual inmate production of the Shakespeare tragedy, and a staged and scripted faux documentary of the audition process. The various Mafiosi, drug traffickers, and killers in the cast, many of them lifers, seem totally at home with the material, dealing as it does with power, treachery, and assassination — and they are free, at least in rehearsal, to riff on a vernacular version of Shakespeare’s dialogue.

Suavely shot and set to a moody jazz score, the movie is spare but slick. The performances, some verging on psychodrama, are amplified by the penitentiary mise-en-scène as when the drama’s imposing Caesar – every inch a jail-house capo – encounters the obsequious soothsayer while traversing the enclosed bridge from one cell block to another, or, alone in a walled concrete prison yard, Antony delivers his eulogy to an audience of incarcerated spectators. Less convincing are the guards watching the “rehearsal” below. When one notes that it’s time for the prisoners to return to their cells, his comrade — caught up in the drama — says, “Let them finish the scene.” They do, reinforcing the notion of the Rebibbia penitentiary as a progressive institution.

The Tavianis give the inmate who played Cassius the last word: “Since I got to know art, this cell has become a prison.” The final credits, however, are more straightforwardly redemptive, noting that two of the imprisoned cast members were inspired to write books and one, upon release, became an actor.