"As soon as this project was announced, and I still see these comments: 'I'm not going to read it. I only like Rose and that's it,'" Richelle told us on the phone last week. "I can relate to that. I've had that happen with authors who end a series I like and then they do a spin-off with another character and I'm like, 'Why can't we do the old ones?'

"But so often with my favorite authors I find out it's not just the characters I'm in love with, it's that style," she added, naming fantasy authors Tamora Pierce and Robin Hobb as two whose spin-offs earned her loyalty.

Of course, this spin-off isn't just asking us to get hooked on new vampires. It's focused on the Alchemists, the group of humans who have dedicated themselves to protecting the rest of our species from knowing of, or being harmed by, the "unnatural" Moroi vampires and half-human dhampirs. In "Bloodlines," all of the characters are out of their element. Lissa is now the Moroi queen, but because of a law that says she needs a living relative in order to maintain her reign, her 15-year-old half-sister Jill is in danger of assassination by rebel groups. Afraid of the implications of a vampire civil war, the Alchemists enlist Sydney to help out as Jill goes to live under cover in a boarding school in sunny Palm Springs. And lucky for "VA" fans, heartbroken playboy Adrian has come along as part of Jill's new makeshift family.

And though we're looking through the eyes of Sydney, who befriended and helped Rose in the last three "VA" books, she's still part of a culture full of prejudices against the fanged ones. It's jarring to hear "vamp lover" slung as an insult after all this time. But that's kind of why Richelle decided to tell this new story.

"Sydney gives this outside-in view, which I think will help readers see more of the world too. Through her eyes it's not normal, and it gives us something that we perhaps hadn't noticed before," Richelle explained. Though she started writing the book from multiple characters' perspectives in an earlier draft (the first chapter of which was made available on EW.com recently), she eventually decided it was sprawling "out of control" and streamlined the story to one point of view.

And there's the other bonus to Sydney: The super-smart, home-schooled secret agent is hilarious as a fish-out-of-water in boarding school. (When a boy tries to ask her out, she thinks he's just asking her opinion on silent movies: "I respect it as an art form but really don't get much out of watching them.")

"That for me is a neat difference, after having written someone so fearless and outgoing as Rose for these years," Richelle said. "There are times when I miss Rose's more in-your-face style, but at the same time it's fun to hear Sydney analyze something like crazy, and she's so smart sometimes, I don't feel like I'm smart enough to write her."

While straight-laced Sydney does manage to get herself tangled in a murder mystery, a dangerous drug ring and a life-threatening situation, "Bloodlines" doesn't come anywhere near heart-stopping frenzy of "VA" books like "Blood Promise" or "Last Sacrifice." That's on purpose, too.

"Even if you look at the first series, the first book and to a certain extent, the second, we're sort of setting up the world," Richelle said. "It's great if you can throw in cliffhangers and dramatic things right off the bat, but I think that before you shake up the status quo, you have to lull readers into it and then really start messing with your characters."

Come back later this week for some spoilery "Bloodlines" goodness from Richelle Mead.

Are you planning on picking up a copy of "Bloodlines"? Tell us in the comments and on Twitter!