Leonardo DiCaprio plays the obsessive billionaire, aviator, and filmmaker Howard Hughes in this enjoyably opulent biopic by Martin Scorsesea grand entertainment that may provoke curiosity about Hughes but doesn’t supply much original thought. With its stylish direction and John Logan’s clever but shallow script, the film totes up a good many Citizen Kane references to little effect. Yet Cate Blanchett delivers a witty and nuanced impersonation of Katharine Hepburn (one of Hughes’s many paramours), and there are colorful and glittering re-creations of the Cocoanut Grove and Grauman’s Chinese Theatre. Best of all is a heart-stopping sequence in which Hughes crashes his XF-11 plane in Beverly Hills, though characteristically the movie doesn’t note whether anyone else was hurt. With Kate Beckinsale, Alec Baldwin, Ian Holm, Alan Alda, Danny Huston, and John C. Reilly. PG-13, 169 min. (JR)