The surest path for a famous actor to win an Oscar? Play another famous dude. The Academy Awards have long held biopics in high favor, and Oscars have feted many best actor winners for their portrayals of historical figures and real-life personalities. Yet Hollywood's biggest night has celebrated its share of fictional figures, too, like Jean Dujardin's silent-movie star in "The Artist" and Denzel Washington's volatile cop in "Training Day." The newest winner being named March 15 likely comes from the latter group. Michael B. Jordan plays twin gangsters battling vampires in "Sinners," Wagner Moura is a researcher on the...