Finally, Sean Penn surrenders.

Sean Penn has long been considered, by many, one of Hollywood's most brilliant, outspoken and dependable actors.

Yet, there's always been something about Penn that has kept me from considering him one of this generation's finest actors.

It comes, for me, to the word "surrender."

Penn has been most acknowledged as an actor for roles in which he simmered on the edge.

Penn's Oscar history?

"Mystic River," in which Penn is a torrential downpour of rage and intensity and for which he took home the Oscar for Best Actor.

"Dead Man Walking," in which Penn simmers with such power and focus that you finally forget his breakthrough performance as stoner Jeff Spicoli in 1982's "Fast Times at Ridgemont High."

Penn proved he could pull off comedy in Woody Allen's "Sweet and Lowdown," and his acclaimed performance received yet another Oscar nomination.

Penn came close to surrendering in "I Am Sam," the 2001 film in which Penn played an intellectually disabled man fighting for custody of his 7-year-old daughter. While the performance received an Oscar nomination, I could never quite escape the feeling that Penn hadn't quite surrendered to the character of Sam and his performance lacked the vulnerability that would have sent "I Am Sam" soaring.

Finally, however, Penn has surrendered and, indeed, he soars as Harvey Milk in director Gus Van Sant's biopic based upon the life and assassination of the first openly gay elected official in America.

To say that Penn's performance is the finest of his career is an understatement. Much like was true when Philip Seymour Hoffman won the Best Actor Oscar for "Capote," Penn's performance as Milk is so astounding, such a complete and utter transformation that it almost seems frivolous to consider anyone else for the Oscar this year. There are other fine performances this year, including Hoffman's own exemplary turn in "Doubt," but I've yet to see a performance that soars so completely and wondrously and with such conviction as Penn's performance in "Milk."

Some misguided critics have lamented Van Sant's return to mainstream cinema, though most have at least had the reasonable intelligence to acknowledge "Milk" as a darn fine film.

I'm not convinced, however, that Van Sant ever sets out to make films that are independent or experimental or mainstream or any of the other labels that we stick upon our movies.

Van Sant is a visionary, artistically true director who makes films with integrity regardless of what they are "supposed" to be or whether or not they fit comfortably into our labels.

"Elephant" challenged our usual viewing habits...so, it became "experimental" filmmaking.

"Last Days" was as much a poem as it was a film...and so, it became a fine example of indie filmmaking.

"Good Will Hunting" had a story to tell and, so, Van Sant created the film that would tell the story.

With "Milk," Van Sant creates a vibrant and heartfelt film that magnificently weaves its way through both the human complexities of the life and times of Harvey Milk while capturing the layers upon layers of San Francisco's late 70's communal experience.

You need not know a thing about Harvey Milk to be completely enthralled with "Milk." In fact, you need not give an iota about the gay rights movement to embrace the film, though, every activist, civil rights group, advocate and change-seeking person across America ought to be running into theatres to see this film.

In "Milk," we are introduced to Harvey as he arrives in San Francisco in 1972 with his lover, Scott Smith (James Franco). The two men open a camera store on Castro Street, and before long it has become a communal presence brimming with ideas, beliefs, thoughts and feelings. This "community" empowers itself and Milk becomes its self-proclaimed mayor. Encouraged by gay activist Cleve Jones (Emile Hirsch), Milk begins to set his sights on public office.

Milk loses once.

Milk loses twice.

Milk loses three times.

Milk wins a seat on San Francisco's Board of Supervisors, thanks largely to his lesbian campaign manager, Anne Kronenberg (Alison Pill). Initially, he forms an easy alliance with San Francisco's mayor George Moscone (Victor Garber) and fellow Supervisor Dan White (Josh Brolin). However, his relationship with White quickly turns sour and White becomes increasingly oppositional.

If you've only read this review and know nothing about Harvey Milk, you still know the end of the story.

I'm not giving away a spoiler. Based upon a true story, we know that Harvey Milk does not survive. Indeed, we know that Mayor George Moscone is also killed that same day.

We know that Dan White was convicted of killing both men.

What Van Sant does so beautifully is that he paints the story of these men with an almost startling yet refreshing honesty.

Van Sant is aided in this effort by uniformly strong performances and the usual stellar camera work of frequent Van Sant collaborator Harris Savides.

I could continue to toss superlatives Penn's way, but what's truly amazing is that Penn is surrounded by equally exceptional performances.

James Franco, who seems to be finding his cinematic way after a few big budget misfires, is funny and sweet and tender as Scott Smith, while Hirsch excels as the activist Cleve Jones. Diego Luna, as a neglected lover of Milk's, is simply mesmerizing.

It is Josh Brolin, in quite the turn from his role as George W. Bush earlier this year, who offers the film's other tour-de-force performance. As Dan White, Brolin is simply astounding as the conflicted White. Whereas so many actors would have been tempted to play White as a caricature, Brolin radiates White's full humanity and captures a man who was simultaneously repulsed by and attracted to Milk and his influential movement.

The script, by "Big Love" scribe Dustin Lance Black, perfectly encapsulates the world in which Milk lived, thrived and, ultimately, died. Black's dialogue is crisp and real, his character development multi-layered and satisfying.

"Milk" isn't an experimental film.

"Milk" isn't an independent film.

Indeed, "Milk" is not a mainstream film.

"Milk" is, quite simply, the best film of 2008.