Starring: Tom Cruise, Cameron Diaz, Peter Sarsgaard Directed By: James Mangold Knight and Day has no real characters, no plot, no-sense of urgency, no point to speak of. Yet, somehow, polished up like Tom Cruise’s bright white teeth reflected in his Persol Havana sunglasses, it very nearly works. Director James Mangold envelops this shiny affair in a retro air, specifically the comedy/action genre so prevalent during the 1970s. In fact, were this film made back then it would likely have co-starred Goldie Hawn in the shrieking Cameron Diaz role and Burt Reynolds as Cruise’s, top off at least three times and seemingly impervious to bullets lead. As loud Julie Havens,…