Elton John Intros New Cameron Crowe Music Doc 'The Union' at Tribeca

Cameron Crowe did more for Elton John with his "Tiny Dancer" homage in "Almost Famous" than a hundred Rolling Stone interviews ever could.

Now he's set to do it again with 'The Union,'  a new documentary which opened up the 10th annual Tribeca Film Festival last night.

The festival kicked off with a free outdoor event outside near Ground Zero in lower Manhattan, which was meant to remind the audience of the original intention of the fest - uniting New Yorkers after 9/11, according to The Hollywood Reporter.

Elton John gave a concert at the event, which also featured the premiere of "The Union." The film tells the story of how John came together with Leon Russell to produce the 2010 album "The Union" under the watchful eye of T-Bone Burnett.

Over 5,000 New Yorkers reportedly attended the concert.

Leon Russell, who was recently inducted into the Rock & Roll Hall of Fame, was apparently not able to attend because of touring.

Known primarily as one of the best session players alive, Russell has played alongside Jerry Lee Lewis, Bob Dylan, George Harrison, Ringo Starr, Eric Clapton, The Byrds, The Beach Boys, Willie Nelson and more.

For John, making the film with Crowe was really a labor of love.

"We just wanted to document a special occasion," told THR. "We really started doing it only for our own use."

Crowe, who has long been interested in the intersection of music and film, starting with "Singles" and "Almost Famous" and including a new doc he's doing with Pearl Jam called "Pearl Jam 20."

"As a longtime fan of both artists, it was a pleasure to spend a year filming their collaboration,” said Crowe.