Leonardo DiCaprio has proven himself a masterful actor, but his performance in Clint Eastwood’s J. Edgar is sure to put him on the same shelf as Sean Penn, Meryl Streep, Viggo Mortensen, Johnny Depp, and Christian Bale – actors who inhabit their roles so convincingly that the real person essentially disappears. As J. Edgar Hoover, who became the head of the FBI in 1924 and remained so until his death in 1972, DiCaprio thoroughly captures the look, the mannerisms, the voice, and the personality. We see a man who took his public image as seriously as his job, as made abundantly clear by a scene late in the film, in which key events in his life are disputed. It’s actually rather cleverly handled. It’s a matter of perception; what others see in you may not be as interesting as how you see yourself.

The film is structured as a meandering narrative, freely shifting back and forth between Hoover’s early days at the FBI and the final years of his life, at which point various typists transcribe an autobiography he’s dictating. He recounts the major cases he personally oversaw, including the Palmer Raids, the kidnapping and death of Charles Lindbergh’s baby boy, and the gangster wars of the early 1930s. To say he “personally oversaw” is not to suggest he acted alone or was even physically present. That didn’t stop him from taking most of the credit. When Melvin Purvis, one of the most effective and respected agents of his time, became a media sensation after successfully tracking down criminals such as Baby Face Nelson and John Dillinger, Hoover’s response was to demote him. He would, in fact, frequently fire or reassign agents he considered objectionable.

I suspect most audiences will go into this movie with preconceived notions about Hoover’s personal life, most notably that he may have been a transvestite and a closeted homosexual. Both are unsubstantiated rumors, although there is strong evidence supporting the latter, not the least of which is his lifelong friendship with FBI associate director Clyde Tolson. Apart from their professional relationship, they would often dine together, attend social events, and go vacationing. Tolson would go on to inherit Hoover’s estate, receive the American flag draped over his coffin, and ultimately be buried in the same cemetery only a few yards away. It cannot be denied that Eastwood and screenwriter Dustin Lance Black are making a case for this aspect of Hoover’s life. But this is not a message film about forbidden love; it’s a portrait of a man who defined himself solely by his reputation.

True enough, it was built and maintained in large part by gathering secret files on the alleged sex lives of prominent public figures, including Eleanor Roosevelt. It’s widely speculated that he did this only for the purposes of blackmail, which would explain how he was able to stay in power for nearly fifty years (and why FBI directors have since been limited to ten-year terms). Publically, he was so militantly anti-gay that he went as far as to track down and threaten anyone who questioned his sexuality. There’s no telling how he felt privately, although the film makes some compelling arguments. Consider a scene in which he’s alone in a hotel room with Tolson (Armie Hammer) and broaches the subject of proposing to actress Dorothy Lamour (who in real life was reported to have had an affair with Hoover). How does this fit with the image of a lifelong bachelor who surrounded himself with good-looking people, had an eye for fashion, and lived with his mother until the day she died?

His mother, Annie (Judi Dench), matronly and domineering, says that she would rather her son be dead than a “daffodil,” like one of Hoover’s old schoolmates. We inevitably have this scene in mind after her death, at which point Hoover tearfully tries on one of her dresses. By my understanding of this scene, he was not trying to emulate the opposite sex; rather, it was an emotional last-ditch effort to recapture his closeness with his mother. This isn’t creepy so much as it is sad and desperate. In that moment, we pity him.

The other woman in his life was Helen Gandy (Naomi Watts), who, after a few unconventional dates and an awkward marriage proposal, would go on to become his permanent personal secretary. He entrusted her with his secret files, the contents of which remain largely unknown. No real effort is made to speculate on all the information he gathered, which is fine because this isn’t really what J. Edgar is about. It’s a well-researched period drama, complete with accurate costumes, convincing sets, and appropriately nostalgic lighting and color schemes. Above all else, it’s a superbly acted character study about a man once considered the second most powerful in America – although he could have easily been the first, considering the control he had over elected officials.