This lavish big-budget epic was the pinnacle of a uniquely Italian subgenre, the historical hardcore gore/porn extravaganza. The star-studded cast, perhaps lured by the high-profile involvement of producer Bob Guccione and screenwriter Gore Vidal, includes such luminaries as John Gielgud, Peter O'Toole, and Helen Mirren. Director Tinto Brass, whose similar treatment of Nazi Germany in Salon Kitty won him the job, did his best with the mammoth enterprise, but numerous production problems and re-edits took their toll on the finished product. When Caligula works best, it works because of Malcolm McDowell, whose crazed portrayal of the title Emperor is the embodiment of villainous corruption. McDowell raises his performance level to match the gaudy spectacle around him, which led to charges of overacting, but there are moments when he is absolutely riveting. Some of the cast doesn't fare as well, as O'Toole makes a particularly unsubtle Tiberius. The sex is graphic and steamy, particularly a feverish lesbian interlude between Penthouse Pets Lori Wagner and Marjorie Thorsen (using the pseudonym "Anneka di Lorenzo"), and the various carnival freaks used as atmosphere imbue the film with a grotesque, Fellini-like opulence. There are many memorable scenes and a magnificent score by Paul Clemente, but the heady brew of historical epic, hardcore sex, and gory violence proved overwhelming to many viewers. Still, Gore Vidal's script is surprisingly accurate, and manages to be entertainingly vulgar while bringing a rather loathsome slice of human history to vivid life, warts and all. The more explicit scenes were directed by Bob Guccione and Giancarlo Lui, causing both Vidal and Brass to remove their names from the credits.
by Robert Firsching synopsis