On the third anniversary of its premiere, the cast and creator of ABC's "Castle" convened at the Paley Center for Media's PaleyFest 2012 event honoring the show, a fun and lively evening that included an audience Q&A, a song from actress Tamala Jones, a reading of excerpted scenes from the "Blue Butterfly" film noir episode, lots of fun interplay that highlighted the cast's camaraderie, and a screening of the March 19 "Dance With Death," episode, in which a contestant on a "Dancing With the Stars"-like TV show is murdered (fittingly, the episode follows the spring premiere of "DWTS").

Earlier on the red carpet, we got show scoop from cast members and producers, along with what they're all doing to be a little greener on and off the set. For starters, the production offices avoid plastic, print out on double-sided paper, and recycle everything possible, according to producer Laurie Zaks. Recycling is in place on the set too, "and we use green materials when we can — it's not always possible but it's something we're conscious of," said show creator Andrew W. Marlowe.

Stars Stana Katic (Beckett) and Seamus Deaver (Ryan, pictured right) founded the Alternative Travel Project in October 2010 to promote going carless for the environmental and health benefits, and are encouraging others to follow their lead by going car-free for a week this month and walking, riding a bike or taking public transportation instead. According to Katic, who's been walking to work, which takes her about an hour, "people across the globe are dedicating at least one day without their cars, and there are some really beautiful relationships that have formed," she said, mentioning two engaged couples she knows of. She's also on the order list for a three-wheeled electric vehicle called an Arcimoto. As for playing Beckett, "I think she's a beautiful, strong woman who makes mistakes and tries to do her best. I love people with flaws who are trying to grow and keep progressing both personally and professionally and I think she's great female role model," Katic said.

Deaver gets 32 miles to the gallon with his Audi, but has been leaving it in the garage to run or ride his bike the two miles to the studio. "You get to clear your head, think about your day, and see your city in an interesting and different way. There's a lot of aspects to it: getting to know your neighborhood, learning to live locally, carbon neutralizing yourself," he said. Other cast members do their part in different ways. Molly Quinn (Alexis), 18, has been a vegetarian her entire life, and Penny Johnson Jerald (Chief Gates) recycles, composts, and uses the compost in her garden.

Jerald ("24"), who joined the cast this season, admits she found it a little difficult at first to adjust to the established rhythm of the show, but she's relishing playing the "strong and solid" Gates, "the strength and foundation of the precinct," and being a role model for women of color and women in general. "Because there's such an absence of role models in my own ethnicity, being there shows that if it can happen for me it can happen for you, and I find that exciting and empowering," she said.

For Quinn, the loving father-daughter relationship Alexis has with Castle (Nathan Fillion) "reminds me of me and my dad. My dad is my Castle, my best friend, so it's great to represent that kind of relationship on TV and not be a bad, rebellious daughter," she said. So far, Alexis "has had such problems finding love," and she wouldn't mind remedying that by casting Tyler Posey ("Teen Wolf") or "Mad Men" star Jon Hamm (despite his age) as a love interest. Like Alexis, Quinn is college bound. Currently taking classes at Los Angeles Valley College, she applied to the University of Texas and wants to study the behind-the-camera aspects of show business. "I never thought I would but I've begun to see the beauty of it. I want to learn every aspect of this business because I love it."

At the core of "Castle" is the relationship between cop Beckett and crime novelist Castle, and the chemistry Katic and Fillion bring to the characters. So far they've flirted a lot but haven't consummated their attraction, something that the producers think is inevitable. Zaks points to Fox's "Bones" as an example of a show that made their leads' relationship official with no ill effect. "I don't think it's the kiss of death," she said, and Marlowe echoed that belief, saying he's "not someone who believes in the curse of 'Moonlighting.' There's a lot of storytelling we can do."

Marlowe won't pin down the timetable for the Big Moment, believing "characters organically suggest where they want to go. The challenge for us is to find reasons for them not to be together and struggle with when they should be together. We just want to be true to who these characters are and that any obstacles that get in the way are natural obstacles. As long as we feel we can credibly do that there will come a time where we don't keep them apart. When that time comes it will open up new opportunities in the storytelling because the characters will act differently and get on each other's nerves in different ways. The next evolution in their relationship will be just as fun," he promised.

Other upcoming developments this season include an April guest appearance by Fillion's "Firefly" co-star Adam Baldwin as a gang task force detective named Slaughter, a zombie-themed episode, and an "emotionally powerful" season finale. "This has been a season of secrets," said Marlowe. "Castle and Beckett are both keeping significant secrets from each other and as we get to this last run of episodes the secrets will start to come out and both characters and all the characters around them will have to deal with the emotional consequences." The ongoing thread of the murder of Beckett's mother "is something we'll be touching on by the end of the season. Whenever that arises it puts Beckett into a very emotionally raw situation," he added, noting that the matter of Castle's missing father, who might have been in the CIA, will also be explored.

With the noir-esque "Blue Butterfly" episode, which gave the actors the chance to play different, period versions of themselves and included some musical elements, scoring with fans and critics, Marlowe said he'd consider a musical episode down the line. He showed the Paley audience a preview of the next tie-in Richard Castle novel, "Frozen Heat," and said that a new Castle e-book series of novellas featuring ex-CIA operative Derrick Storm will be published by Hyperion, starting with "The Brewing Storm" in May, with two more to follow in July and August.

Photos: Kevin Parry

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This is one green 'Cast-le'
The cast members of 'Castle' are leaving cars at home, recycling, composting and going vegetarian.