Anthony LaPaglia in Without a Trace's "Deep Water."
For the last five years, Aussie-born Anthony LaPaglia's life has been intertwined with that of his Without a Trace character, FBI missing-persons agent Jack Malone. On the CBS series' March 11 episode, "Deep Water," LaPaglia will be credited not only as the popular procedural's lead, but also as that episode's writer.

"I never really had a burning desire to write or direct or any of that," LaPaglia tells TV Guide during a quick on-set lunch break. "It's the fifth year of the show and while I like the acting part of it, I was starting to get a bit itchy. I was sitting around one day with the guy who does my make up, Mike Mills, and we were talking about different stories that were out there."

Without a Trace often focuses on stories based on real-life incidents, and it was the Lacy Petersen story — specifically the queer post-disappearance behavior of her husband, Scott — that intrigued LaPaglia. "I got caught up in that case, and him and his behavior. Why would he behave the way he behaved [after she was missing], especially under the scrutiny of the FBI and everyone? Why would he sell her car after two weeks? Why would he turn the nursery into an office?"

At the same time LaPaglia found himself intrigued by the Petersen case and the actions of the main players, he was also very interested in a story he'd heard about the government wanting to open up wildlife and nature preserves to oil drilling. Those issues, further combined with the mythic tale of Joseph Kennedy's "stage-parenting" of his children into political careers, eventually dovetailed into a solid script idea.

The actor opted to keep those who knew about his project to a few, only hiring a researcher to make sure that historical, legal and political issues were handled accurately. He also made sure that Without a Trace's FBI consultant reviewed the script.

Since LaPaglia doesn't type and was writing the script in longhand during breaks in between scenes, he also had to hire a typist. Eventually, after eight months, he was ready to turn the script into the show runners, who liked the idea and wanted to move ahead with it, with some tweaking.

LaPaglia then spent two full weeks working with three or four writers, and eventually partnered up with scribe Byron Belasco for the finishing touches. "Byron was very good," says LaPaglia who considers his co-writer a good friend, too.

The final script "ended up being quite different than the one I turned in," the actor notes, "[but] it had all the original elements, with a better story. It was better-structured, more interesting. Mine was actually too political, and there wasn't enough in there about personal relationships. That's what we worked on the most, personalizing the main characters."

Despite what seems like an arduous task — LaPaglia says he's seen the episode so many times he's lost all objectivity — he "enjoyed it a lot actually," and now realizes there's a big learning curve. "I always have a lot of respect for writers. They do a new show every week. I really learned a lot about structure. I enjoyed the process of writing and problem solving."

Among the things LaPaglia found difficult was "when you got into physical production, you'd be sitting in a meeting and we'd be told, 'You can't have that, it's too expensive,' or, 'It doesn't fit into the shooting schedule.' You can really see where a script can go wrong. You have to really stay on top of it or you end up with Frankenstein's Bride, all stitched together."

Actually shooting his first script exciting, LaPaglia says. "I made sure I was there from dusk to dawn, from crew call to wrap," he recalls. "I made sure I was there, because I wasn't just acting in it. I was there to consult with the actors, making sure everything worked for them. It was exhausting, and I was on the lot for hours."

After five years of playing Malone, LaPaglia says the character was easy to write. "I know him pretty well, and all the other main characters, too. I know what they enjoy saying and what they don't. My castmates were incredibly supportive, too. Everyone was, from the very top to the bottom."

Reflecting on the experience as a whole, LaPaglia says that going with his gut was a critical first step. "I always think you should write from the heart," he observes, "because if you start writing what you think someone else is going to like, then you get into trouble."

The LaPaglia-penned Without a Trace episode, "Deep Water," airs Sunday, March 11, at 10 pm/ET.

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