Limited parts sometimes turn into regular gigs

Guest starring allows actors to join a series midstream for an episode or two and then move on. In some cases, however, if the TV gods are smiling upon you, the venture can lead to a full-time role.

Kate Walsh is a notable example, going even one better. She segued from guest to regular after the first season on “Grey’s Anatomy,” then landed the lead in spinoff series “Private Practice,” which premiered last fall.

“Initially it was meant to be a five-episode arc, a little blip on the radar of Derek and Meredith,” Walsh says. “So it was definitely like hitting the jackpot when they called and said, ‘We’d love for you to be a series regular.’ It was great because I was bummed that a comedy pilot I did didn’t go, and then this show, which I really loved being on, asked me back. That just never happens.”

While Walsh is a high-profile example of moving from guest to regular, it happens more often these days with actors who don’t get the headlines that someone like Walsh receives. Most examples are in serialized shows, where a character seems to resonate with both the writers and viewers.

Jack Coleman, whose role as a shadowy figure in the “Heroes” pilot turned out to be Claire’s father, says, “It’s not like ‘CSI’ or something procedural, where you bring in a guy as a guest star and never see him again because his story is told. These stories are ever-unfolding; characters tend to get tied into stories.”

Coleman was hired for five more episodes in season one but soon heard that he might earn a contract role. “The character started making himself, if not essential, certainly an important part of the unfolding mystery,” he recalls.

In addition to Coleman, others on “Heroes” have made the transition: Cristine Rose and James Kyson Lee made the jump as well.

On “Lost,” Michael Emerson was originally slated for three episodes in 2006 — cast by the showrunners, coincidentally enough, based upon his guest-starring stint as a psychotic killer on “The Practice” — but quickly became integral to the intricate mythology of the series.

His first inkling that Ben might become a permanent character came while shooting an interrogation scene. The director asked Emerson to hint that the person pulling his strings was incredibly powerful and frightening, and the actor felt he had an intimate perspective on what made the character tick.

“I said, ‘What if that person turns out to be me?’ He looked at me, blinked a couple of times and said, ‘I can’t talk about that,’ and walked away. I thought, ‘Am I onto something here?’ ” Emerson recalls.

Olivia Wilde, Kal Penn and Peter Jacobson had a different experience on “House,” being part of a group of actors vying for three full-time roles. The situation was eerily similar to their characters — physicians competing for fellowships to work with Hugh Laurie’s irascible Dr. House.

“It was kind of helpful for the work we were doing that our own lives were paralleling it so much,” Wilde says. Over their first few episodes, producers watched to see how the actors developed their characters and interacted. “It ended up being kind of an eight-episode audition.”

Wilde appreciated having a part in one episode of ratings-champ “House,” so the eight episodes leading up to learning which three actors would become regulars was a thrill.

“We all felt very lucky to have any shot, knowing if we got to stay it would be a huge life change, an amazing job,” she explains.

‘Rough out there’

Some actors enjoy job-hopping, but Coleman says most actors prefer a steady paycheck.

“It’s like manna from heaven because it’s rough out there,” Coleman says. “I’ve got a lot of really wonderful actor friends who are struggling.”

Emerson, who was content with a career full of guest spots in addition to legit work in New York, adds, “I think every actor nurses a little bit of a fantasy that they’ll nail a thing so well that the show can’t figure out how to do without them, or that the viewers will want more.”

Walsh observes that guest starring — while it can be intimidating being the new kid on the set — is more natural than going through the pilot process in that you’re already on a show that’s gone through the rigors of getting on the air.

“If I had to test for this, I don’t think I would have gotten it,” Walsh says.

Proving herself on “Grey’s” felt completely civilized. “It’s much more enjoyable than going through a massive studio and network test where it feels a little more like war.”

Adds Emerson: “I’m a guy who couldn’t get arrested to do a pilot. There was no way I was going to get on a series through the front door. I was never going to pass all those studio and network tests.”

That’s why Coleman believes a good guest role beats an audition every time.

“It’s like your network test with real people under real circumstances. It seems like not only the best way to get a job, but in some ways the only way to get a series regular these days. The landscape has changed. I know a lot of actors who feel the best way in is through a nice little arc. Then you somehow make yourself indispensable.”

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