When HBO's "True Blood" returns for its second season this summer, expect an increased emphasis on supernatural phenomena beyond vampires and on plot twists which stray from the books, according to actress Carrie Preston.

The new season will feature 12 episodes, and adds new cast members, including Valerie Cruz ("The Dresden Files"), Ashley Jones and Anna Camp. They join Season 1 cast additions Michelle Forbes ("Battlestar Galactica"), Mehcad Brooks and Deborah Ann Woll.

Preston, who plays the redheaded Merlotte's bar waitress Arlene Fowler, promises an expanding story arch that breaks new ground not reflected in the "Sookie Stackhouse" novels by Charlaine Harris.

"Things are going to get a little crazy on the show," Preston said in an interview with SCI FI Wire. "There's going to be a bunch of new sort of supernatural things that are being introduced. Besides the ... the vampires.

"I don't know if I'm at liberty to talk about it in detail, but, we are departing a bit from the books. ... So the writers have really taken the groundwork that they set in the first season and kind of launched from that, and they're fleshing out characters that are minor in the books, and they're ... changing some plot things, and they've really made it their own. ... You're going to see some characters doing things that you're surprised at, which will be fun. So I think the show is going to kind of keep you on your toes, and there's several different storylines that are spinning in the air."

The cast's primary characters naturally receive enticing developments.

"Sookie [Anna Paquin] and Bill [Stephen Moyer], uh-huh, and we're going to follow Jason [Ryan Kwanten]. He's going to kind of veer off the path a little bit. And so we'll be watching that. And then Tara [Rutina Wesley] has gotten herself involved with some questionable characters. And then, of course, you're always going to touch back down into the Merlotte's crowd. ..."

Also enjoying the spotlight is Forbes' Maryann.

"She's going to figure quite prominently this season. ... It's very mysterious, and, I mean, we're still a little confused ... as to what her powers actually are. But, you know, she is a very powerful force."

With such powerful forces lurking in the shadows, the world of "True Blood" is ripe with dangers, leaving the fate of many characters this season in question.

"Some new characters have been introduced, and, you know, it remains to be seen whether they will live or die. That's the thing with being on the show, you just never know: Are you going to make it? Are you going to make it through the season? Especially now that they've departed from the books. Because when I got the job, of course, I read all the books to see if Arlene lives, and she does in the books, but who knows?"