P eter Farrelly’s new film I Play Rocky is about the underdog-with-heart story of how a great boxing movie got made against the odds with its plucky young untried screenwriter allowed to star. So here is a reissue of that 1976 film for its 50th anniversary. It’s a forthright, rousingly idealistic film, wholesome in its essential patriotism, and which unselfconsciously shrugs off the boxing-movie’s gloomy generic inheritance, throwing away its grim traditional baggage of tragedy, cynicism and loss. It also doubles as a love letter to Philadelphia, the cradle of American democracy.

Its writer and insurgent star Sylvester Stallone created the role of Rocky Balboa, a punchy heavyweight fighter just turned 30, making peanuts slugging it out with bums and reduced to collecting debts for the Philly mob; this is an indignity which infuriates his grizzled old trainer and former mentor Mickey (Burgess Meredith) who once saw greatness in Rocky and is disgusted to see him selling out.…