Randi Kleiner felt like an 8-year-old at her birthday party as she fretted inside the Sie FilmCenter. It was 2015, the opening year of the SeriesFest TV festival and, as with a birthday party, there was no guarantee people were going to show up.

” ‘Is anyone actually coming?’ ” the festival co-creator recalled wondering as she unlocked the doors at the theater on East Colfax Avenue. “I was anxious.”

Not only did people show up that first year, they’ve also continued to blow past her expectations. Now in its 10th year, the nonprofit SeriesFest draws more than 12,000 attendees annually and commands a $2.7 million budget. Kleiner expects attendance to grow by another 2,000 this year, based on current ticket sales for the public event.

SeriesFest, co-created by Kleiner and Kaily Smith, returns for Season 10 May 1-5, with dozens of screenings, panels, awards and even a “Cowboy Carter”-themed Beyoncé dance party at Red Rocks Amphitheatre on May 5, featuring Grammy-winning Young Guru (Jay-Z’s tour DJ). Past SeriesFest events there have featured performances from Stevie Wonder, Lady Antebellum (now Lady A), Chelsea Handler, En Vogue and Common.

This year’s anniversary event takes place mostly at the Sie, with another high-profile slate of guests and programming, including its first-ever gala and honors for actor Minnie Driver, SAG-AFTRA, Shonda Rhimes’ Shondaland company, and a celebration of 20 years of “Grey’s Anatomy” (with cast members James Pickens Jr., Kevin McKidd, Caterina Scorsone and Kim Raver).

The fundraising soirée bolsters SeriesFest’s reputation as a reliable, innovative spot to gather in an industry beset by head-snapping change. As prestige TV continues to move almost entirely to streaming, and the industry grapples with the staggering effects of the pandemic, last year’s Hollywood strikes and artificial intelligence, SeriesFest continues to look smart by marching boldly into a complicated, uncertain future.

“Certainly since the strikes last year, and with the IATSE (film-crew union) strikes looming on the horizon, there’s been a slightly pervasive sense of doom and gloom in my industry,” said British-Nigerian actor Chiké Okonkwo, who returns this year for a live table read of “Grave Affairs” and as a juror in the Drama category of the Independent Pilot Competition. He’s lately been seen in the last three seasons of NBC’s “La Brea,” and is a past award winner at both SeriesFest and the Denver Film Festival.

“I for one don’t subscribe to that doom and gloom,” he said. “We always need stories in a communal setting, but we also love to dig into stories at home and on TV, so this offers different ways of seeing those stories. I’m in awe of the drive and creativity to get these things made against all odds. It makes me optimistic that these people can find audiences.”

Streaming networks and production companies have snapped up independent pilots that premiered at SeriesFest, including “Cooper’s Bar” (AMC+); “Everyone Is Doing Great” (Apple TV+); “Dreaming Whilst Black” (BBC and Showtime); and “Generation Por Qué” (acquired as a short on Max). Creator Emil Pinnock, for example, also signed a blind-script deal with Blumhouse Television and has been tapped to pen an untitled Daymond John project (he’s one of the sharks on “Shark Tank”), Kleiner said.

That’s the result of hard work and a commitment to support new and diverse voices, SeriesFest veterans say. Even with the annual celebs and major title launches — the Paramount+ hit “Yellowstone,” starring Kevin Costner, officially premiered at a SeriesFest screening at Red Rocks Amphitheatre — SeriesFest is a nonprofit that supports young and upcoming women, BIPOC and other directors with mentorships and education.

Kleiner praised the Shondaland production company for taking on SeriesFest luminaries such as Tamika Miller. She won SeriesFest’s highly competitive Women Directing Mentorship with Shondaland and went on to direct three episodes of the acclaimed “Station 19.”

Alysia Reiner is a SeriesFest veteran who’s returning this year for “The Methods of Multi-Hyphenates” panel, along with actors Christy Carlson Romano (“Kim Possible”) and Michelle Hurd (“Star Trek: Picard”). For other veterans of the industry, the festival is essential for reaching new creatives and executives, given that it draws from a fast-growing, global pool of talent flowing from India, China, South Korea, Mexico and other U.S.-crossover markets, she said.

“You have a spectacular mix of people in front of and behind the camera,” said Reiner, who has appeared in seminal prestige-TV shows and streaming hits such as “Orange Is the New Black,” “Better Things,” and the Disney+ series “Ms. Marvel.” Her instantly recognizable face joins Jane Seymour (“Dr. Quinn, Medicine Woman”); Mark Duplass (“The Morning Show”); Jocko Sims (“New Amsterdam”); closing-night comic Hasan Minhaj (“Patriot Act”); Patrick Macmanus (“Dr. Death”) and many more.

“The truth is, our industry has contracted a little bit post-COVID and post-strike,” Reiner said. “Less is being made on that big-budget level … we’re in a real reshuffle of streamers and networks. So it’s deeply empowering when artists are reminded by SeriesFest that they don’t have to wait to create. They can make their own content. … It wasn’t like that when I was a baby artist.”

Plenty of film festivals now offer TV sidebars, Kleiner said, but SeriesFest was one of the first and only to focus exclusively on television. She’s seen the lines between TV, film and various digital media get thinner in the last decade. But her event isn’t just “the Sundance of TV,” as SeriesFest boosters have called it over the years, but an industry leader whose example is increasingly followed (including at South by Southwest in Austin, Texas, and Sundance Film Fest in Park City, Utah).

And yet SeriesFest remains one of the only places to see new TV pilots — network or independently produced — and mingle with industry types ranging from actors to soundtrack supervisors, costumers and directors, said Britta Erickson, a SeriesFest board member and film producer who formerly directed the Denver Film Festival.

“I’m proud of the fact that it came to Denver,” she said, noting that the co-founders shopped around before deciding on the Mile High City. “It was something that was missing in this market, and it felt like the right place, since we’ve been called the cable capital of the world. Now there’s this TV development pipeline that never existed and it’s launching careers and exposing new talent. The ecosystem really does start here.”

“Many networks have moved away from the traditional pilot season, so this is an incredible platform to discover new talent,” Kleiner said. “We’re showing 45 independently produced pilots, and with an audience in attendance, you can really do that litmus test right away.”

Kleiner said charitable giving is down, presenting a challenge for the festival’s continued growth, since it makes up a good portion of the budget. Resources are constantly being divided between fast-growing concerns, such as emerging crossover TV markets in Asia and Spain, prestigious competitions, and live events. But the emphasis remains on new and untested talent that proves itself worthy of national-level attention.

“We’re a small staff of six full-timers, though it grows to many more during the festival, so any programs we do always have an underlying thought to diversity, participation and social initiatives,” she said. “Most executives in industry leadership are white men, and that’s just the way it’s been. SeriesFest can’t change that, but we can show people some other ways of doing things, because we’re not just a festival. We’re a year-round arts organization now.”

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