The tension between a powerful social hierarchy and an unconventional hero, often an underdog, provides a frequent source of mid-20th-century American comedy. The friction arises in Mary Chase’s Harvey, Abe Burrows, Howard Teichmann and George S. Kaufman’s The Solid Gold Cadillac, Philip Barry’s Holiday, and Thomas Heggen and Joshua Logan’s Mr. Roberts. The sympathy for the heroes of those comedies is a foregone conclusion: they are on the side of the angels, as it were. But that’s surprisingly not the case in George Kelly’s The Show-Off, a hard-edged 1920s work admirably revived by the Peccadillo Theater Company. Kelly’s title character, Aubrey Piper, is a great creation, an annoying rascal and a liar, and one waits impatiently for him to get his comeuppance.