James Gandolfini's Death: Hollywood Remembers the 'Sopranos' Star

James Gandolfini Headshot - P 2013
Getty Images

James Gandolfini Headshot - P 2013

UPDATED: "One hell of an actor," Albert Brooks wrote on Twitter, while Christina Applegate added, "I am so deeply saddened by the untimely passing of sweet James Gandolfini!"

Hollywood was in shock Wednesday upon learning the news that James Gandolfini had suddenly died.

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Gandolfini, who made his mark on TV history as the troubled crime boss on HBO’s smash drama The Sopranos, reportedly died of a heart attack. He was 51.

Twitter instantly was flooded with tributes to the actor, who also appeared in such films as Zero Dark Thirty, The Incredible Burt Wonderstone, True Romance and The Mexican.

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Among those paying tribute:

Jeff Daniels said a statement to The Hollywood Reporter: “If Broadway has a version of a guy you want in your foxhole, Jim Gandolfini was mine. During our time together in God of Carnage, we played 320 performances together. He didn't miss one. Sadly, I now miss him like a brother.”

Patricia Arquette: "My heart goes out to his family. James was incredibly talented and I feel very fortunate to have had the chance to work with him. He was very committed during the shooting of True Romance. I remember Tony Scott saying he slept in his suit in his car to stay in character. His work as Tony Soprano was flawless. It is a real loss to the creative community."