For a few rash moments, the big TV networks said they would do more dramas that were NOT about cops or courts.

Then they retreated: They would do crime shows, the same as always; they would, however, have quirkier cops.

"It's part of people reacting to the (shows) that don't have an element of characterization," said Andrew Marlowe, creator of ABC's "Castle," which debuts tomorrow.

For many shows, the case has been all that mattered. NBC's "Law & Order," CBS' "CSI" and others simply followed the clues.

Lately, that has changed a little. Some shows — "Bones," "Life," "Medium" and more — gave more quirks of their main characters.

That peaked this fall, when CBS' "The Mentalist" became a breakout hit. Now "Castle" hopes for a similar audience.

"The scripts were being written at the same time," Marlowe said, but the writers' strike intervened. CBS rushed "Mentalist" onto the fall lineup; ABC held most of its shows for mid-season.

As a result, "Castle" almost seems like a clever copy: Like "The Mentalist," its title character is an urbane chap with no police training. Working with a skeptical female cop, he brings only his observation skill.

In this case, Rick Castle is a novelist. "He's kind of in his own world," said Nathan Fillion, who plays him, "but he's a clever guy."

And now he's at a turning point. "He's killed off his best-selling main character, because he's grown bored with that set of novels," Marlowe said. "And he's looking for new inspiration."

Then he bumps into Kate Beckett, a police detective who could be his new role model.

She works carefully, said Stana Katic, who plays her. "She does have a history with (an) unsolved crime. It became really important for her to create a case that would never fall apart in court."

He has none of that seriousness. "Every day of his life is a field trip," Fillion said. "He's a child inside."

Fillion, 37, is drawn to offbeat acting, including TV ("Firefly"), movies ("Waitress") and the Internet ("Dr. Horrible's Sing-Along Blog"). He also does straight roles, including a "Desperate Housewives" stint.

"They were very kind to me," he said. "But I spent a lot of time sitting around in a living room saying, 'Uh-huh. Yes. That's right. Well, I'll back you up on that.' "

Now he's doing much more. "I wanted to have fun every day," he said.

Katic, 30, has been handed serious roles so far. She's Canadian (as is Fillion), with a name that reflects her dad's Croatian roots. After guest roles in "24," "Heroes" (as Hana Geitelman) and more, she co-starred in Noah Wyle's third "The Librarian" movie.

She also may be the only person to describe "Castle" as "Lubitsch-esque."

That's a reference to Ernst Lubitsch, a noted director in the 1930s and '40s. "Lubitsch always brought this classic kind of subtle sexuality to his characters," Katic said.

For more recent Hollywood heroes, one scene in the first episode has Castle chatting with other writers. Those are real-life novelists James Patterson and Steven Cannell, playing themselves.

That part was fun for Rob Bowman, who directed the pilot and produces the series. Cannell, Bowman's godfather, is a former TV producer whose shows focused on quirky characters.

These days, Bowman is best known as director of the "X-Files" movie. One of his first jobs, however, was to re-record Cannell's "Rockford Files" episodes on half-inch tape.

"I've seen every episode of 'Rockford,' " he said. "I don't remember, really, any of the plots. I remember (Rockford) and his relationship with his father and his buddies down at the station, and that's what drew me."

With luck, it's the sort of thing that will draw people to "Castle," too.