PARK CITY, Utah — News of the tragic death of 28-year-old actor Heath Ledger shocked actors and filmmakers at the Sundance Film Festival on Tuesday (January 22). The revelry of the festival, a celebration of the best of independent filmmaking, was instantly muted as those who knew and revered him spoke to MTV News.

"All I'll say is, I send total love to the family," said Josh Lucas. "It's too painful for me."

"Oh man, it's ripped through Sundance," sighed veteran actor William H. Macy. "Everybody's talking about it."

In town to promote his latest documentary, "Made in America," Stacy Peralta — who wrote "Lords of Dogtown," which starred Ledger — told MTV News he was still in disbelief at the news. "When I heard Heath passed, I was just shocked," he said, explaining that he heard the news via text message. "It can't be possible. How could that possibly happen to him? He was young. He was vibrant. He was healthy. He had an incredible career and a child. I'm shocked."

Bijou Phillips, clearly moved by the loss, compared the tragedy to the recent death of her friend and frequent co-star Brad Renfro. "Brad Renfro also died this week, who I did three movies with," she said. "It's just crazy. Two young, really talented actors die in their sleep in the same week? It's just not cool. I don't know what's going on, but it's got to stop."

Actor and director Clark Gregg, whose film "Choke" features Phillips, said the entire cast learned of the loss together, and despite not knowing him well, everyone was deeply affected by the news.

Phillips, who had met Ledger a few times, turned her thoughts to the child Ledger leaves behind, 2-year-old Matilda. "Career is great, performances are great. When these guys go and leave little kids behind, that's when I go, 'Ugh, those little kids!' " she said.

"He should be proud of the legacy he left behind," insisted Jason Ritter. "[Ledger] seemed to make acting choices with integrity; he didn't seem to just take the big movies with the big bucks. He took movies that challenged him as an actor, he did a fantastic job, and he seemed like a really great guy as well."

"If he had done nothing but 'Brokeback Mountain,' he would be remembered for a long time," marveled Macy, who wrote and starred in "The Deal," which premiered yesterday at Sundance. "It was the most stunning performance I'd seen in a long time. My wife [actress Felicity Huffman] is from the West, and she couldn't believe his performance. It's shocking, it's sad. Felicity said it best: 'Sometimes, with talent like that, it comes with a dark side.' And I guess it got the best of him."

Describing the actor he saw on the set of "Lords of Dogtown," Peralta said, "He was open. He was kind. He was considerate." Though a preliminary autopsy was inconclusive and conflicting reports circulate about the cause of death, Peralta lamented the pain he surmised Ledger was in. "There's a fallacy about being famous. It's not what we think it is. The only value in life is the value you share with people. I just hope he's OK now. I hope Heath Ledger is resting in peace now.

"What's so sad for him is, as far as an actor is concerned, he was finally discovering the talent that was within him," Peralta continued.

Ledger's next film is the hugely anticipated Batman sequel "The Dark Knight." His haunting performance, only glimpsed in trailers, was already being touted as a clearly inspired turn. "Choke" actress Gillian Jacobs admitted, "It's going to be really difficult to watch that movie." Putting the tragedy in the context of her surroundings, she continued, "It's difficult in the midst of this film festival that's a celebration of everything we love about this business. Tragically, this isn't an unfamiliar tale within Hollywood."

"Absolutely," Ritter said when asked if he'll be seeing "Dark Knight." "I heard he was incredible in it; I've heard that for months now."

In the end, the words that seemed to be on everyone's lips in Park City were the "what might have beens?" and the "what ifs?" Shaking his head, Peralta articulated what many were thinking in the snow-covered landscape of Utah: "He left so much potential behind. Think of what he could have done."

"He'll be missed," said Macy. "I'll never get to act with him. I'm sad."

(Watch Heath Ledger talk about his evolution as an actor in a 2005 interview.)