If you thought Rosewood was the creepiest zip code in Pennsylvania, well, you were wrong. Welcome to Ravenswood, where generations of townsfolk have been plagued by a mysterious curse, with no end in sight — until now.

A spin-off of "Pretty Little Liars," "Ravenswood" follows five young strangers (including "PLL" regular Tyler Blackburn) as they work to unravel the town's supernatural secrets...before it's too late.

The show is the brain-child of "Pretty Little Liars" executive producers I. Marlene King, Joseph Dougherty and Oliver Goldstick, who were toying with the idea of a new scary series when ABC Family came calling for a spin-off of their teen hit.

"We love ghost stories, and I think we've all wanted to do a kind of scary show, and at the same time, ABC Family came to us and said, 'We'd like to do a 'Pretty Little Liars' spin-off,' and we kind of merged the two," King explained. "We were like, let's get to have our cake and eat it too. Let's do a scary spin-off of 'Pretty Little Liars.' "

King then approached Blackburn, who had been playing Hanna's long-suffering boyfriend, Caleb Rivers, going on four seasons.

"It came very casually," Blackburn recalled of being approached about the spin-off. "I mean, it was one day on set, Marlene pulled me aside, and she was like, 'So we're developing this show with you as the lead, and we don't know too much about it. We don't know if it's even gonna get picked up.' It was so nonchalant that I was like, is she messing with me? What's going on here?"

But King and the network were as serious as an A-attack.

"Four days later, I think it was, she called me and she was like, 'Well, they green-lit it, so get ready,' " Blackburn said. "It was hard to wrap my head around, and it really was a little surreal until right up until I came here."

Here being New Orleans, where the show is shot—a perfect setting for a series revolving around all things thrilling and chilling.

Producers then set about building a cast around Blackburn, a sort of Scooby-Doo gang that would help him investigate the town's troubling goings-on.

His character's first ally is Miranda (played by Nicole Gale Anderson), a girl Caleb meets on the bus to Ravenswood, who's on the hunt for her long-lost uncle.

"Once we get there, I actually run into Hanna and have some scenes with her in the haunted house," Anderson explained of the "PLL" cross-over. "We kind of stick together to get through all the craziness, and once the liars kind of do their business there, they leave, and the storyline kind of sticks around with Caleb and Miranda finding these really mysterious things that they kind of want to unlock the truth on and kind of work together to find out the truth behind their past."

Enter townies Remy (Britne Oldford), Luke (Brett Dier) and Olivia (Merritt Patterson), who round out the fab five. Of course, these three are shouldering worries beyond just the curse, with Remy's mom recently returned from Afghanistan and twins Luke and Olivia mourning their murdered father.

And whether you're a "PLL" fan or a newbie to the proceedings, Blackburn said there's something in "Ravenswood" for everyone:

"I feel like most people are going to want to watch this because it has a great combination of — it does have a spiritual and supernatural aspect, and it touches on real-life issues, as well: family, friends, love, loss, trials and tribulations, and there's such a wide array of characters that somebody will be able to identify with somebody in this cast in some way."

"Ravenswood" premieres on Tuesday at 9 p.m. following the annual "Pretty Little Liars" Halloween special airing at 8 p.m.