HOLLYWOOD - The very idea of a spec script - an original script written by an aspiring or low-level TV writer for a show already on the air - is one of the television industry’s great paradoxes.

A good spec will both stand out from the 50 or so others waiting to be read and fit right in with the world already established by the show. It will simultaneously demonstrate the writer’s voice and the writer’s ability to adopt the voice of existing characters.

And don’t even think about submitting a spec of the show you actually want to get hired for.

If you’re hoping to get staffed on The Office, say, send in a script for My Name Is Earl or Arrested Development because many show-runners won’t read specs of their own series to keep from being accidentally influenced.

To help navigate this sometimes incomprehensible world, former Buffy the Vampire Slayer and Ellen writer Jane Espenson has started Jane in Progress, a blog on her fan site that serves as a guidebook of sorts. Each day Espenson uses an example from her life to talk about the importance of good character names, how to tee up a joke, or ways to incorporate metaphors into script writing.

Espenson, 42, is thin and wry and smart and talks like a TV character - quickly and with lots of jokes packed into long sentences. Since Buffy went off the air three years ago, she’s written for Battlestar Galactica, Gilmore Girls, The O.C., Tru Calling, Jake in Progress and The Inside, and she recently started on Andy Barker P.I., a single-camera half-hour comedy starring Andy Richter.

"Jane still retains the sense of excitement about writing she had when she started," said Jeff Greenstein, who ran the writing room at Will & Grace for seven years and worked with Espenson at Jake in Progress. "It’s very easy in this business to become cynical and jaded, and fear and revile the new people coming up through the ranks. But Jane has really embraced the neophytes."

And while she’s had experience in many genres, Espenson said she is especially drawn to sci-fi and comedy.

"Jane... really knows how to bring the funny," said Paula Carlson, a fan from Espenson’s Buffy years and the webmaster of her fan site, Janeespenson.com. "No matter how serious a story she’s telling, she always throws in something to funny it up."

As professional TV writers go, Espenson is pretty famous. Her five years of writing for Buffy earned her a devoted fan following that still monitors her career.

"Buffy in particular had this cult of the writer," said Espenson, eating a vegetarian pizza in the Westwood apartment she shares with her boyfriend, writer and political blogger Bob Harris. "Entertainment Weekly came and did a big profile on us and took a big two-page spread photo of just the writers. And we all got fan clubs with names. I had Jane’s Junkies."

Last January, as the John Stamos comeback vehicle Jake in Progress was winding down for the season, Espenson told Carlson she’d like a place on the page for a blog. Her idea was to write tales from the writers’ room and, because of her built-in fan base, it didn’t take long before she was getting 40,000 hits a week. Then Jake was getting canceled or not getting canceled and was finally placed on a seemingly permanent hiatus.

So she decided to start blogging about how to write specs. "I thought I would just give little nuggets of writing wisdom until I ran out, and I figured it would probably take at least a month, but I haven’t run out yet."

The idea that permeates Jane in Progress is that a spec script is a unique animal because its intent is to impress a specific reader, not to be performed and filmed for a wide television audience.

People "talk as though writing a spec is the same thing as writing a freelance episode, and it isn’t," Espenson said. "Writing for a reader has its own special challenges."

Beyond the insider tips, Espenson also gives her readers entree to the television writing world, a weird and contradictory place where writers stay at the office until all hours, hard at work trying to be funny, and where a person can get a "written by" credit regardless of whether any of his or her original dialogue made it into the final script.

By dropping insider lingo like the "A-story line" or "beats" in a script, and talking about "the room," Espenson is arming fledgling writers with the ability to talk like they know what they are doing.

Now all they need to do is write the most original, conforming, distinctive-yet-familiar spec script that they can.