The main actor in the movie "Caligula" is Malcolm McDowell, who plays the character of Caligula. Some other actors include Teresa Ann Savoy, who plays Drusilla; Guido Mannari, who plays Macro; and John Geilgud, who plays Nerva.
The emperor Caligula was famous for his violent methods in order to gain the throne. During his reign, he did many things to show his insanity, including giving his horse a political office and executing or humiliating anyone he didn't like or anyone who disagreed with him. While there are many versions of the Caligula story, this 1979 film is the best-known movie adaptation.