The sudden death of director George Hickenlooper late last week has elicited a flurry of reactions from his Hollywood colleagues, most notably his "Casino Jack" collaborator Kevin Spacey. Hickenlooper, who died in his sleep from unknown causes last Friday, directed Spacey in a biopic about Jack Abramoff, a Washington, D.C., lobbyist currently serving a prison sentence on fraud, conspiracy and tax evasion charges.

"I can't believe he's gone because George was so alive, bubbling with energy, drive, commitment, an open heart and a brilliant sense of humor," Spacey said of his director's passing, according to TheWrap.com. "He was one of a kind."

"My experience working with him was nothing short of fantastic: from our prison visit with Jack Abramoff, to script meetings, pre-production discussions and finally our first day of shooting," the actor continued. "From that day until our last event premiering 'Casino Jack' in Toronto last month, he was a joy to be around. His sensibility and outlook served his everyday. All of us who knew him, who had the chance to collaborate with him, who saw the child in him that he never lost -- always looking at life with wonder and curiosity -- will miss him with enormous admiration and affection."

Others have echoed Spacey's sentiments, with "Supersize Me" documentarian Morgan Spurlock commenting that "he was a great talent and an amazing guy." Hickenlooper's wife, Suzanne, has released a statement as well, saying, "He had a great creative talent, a generous spirit and loved life and people more than anyone I know."

Hickenlooper was found dead on Saturday in Denver, Colorado, where he was presenting "Casino Jack" at the Starz Denver Film Festival and supporting his cousin John Hickenlooper's campaign for governor of Colorado. "Casino Jack" is currently scheduled to arrive in theaters in December.

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