'Pretty Little Liars" Alison is alive! Now what?

NEW YORK  — "Pretty Little Liars" has hooked viewers with the twists and turns of four friends who are repeatedly tormented and tricked in their fictional town after their queen bee best friend Alison DiLaurentis is murdered.

That's why many fans were shocked in the show's annual Halloween episode when it was revealed (spoiler alert!) that Alison was alive and had been in hiding this whole time.

The series resumes its fourth season Tuesday at 8 p.m. EST, and actress Sasha Pieterse (Peter-Suh), who plays Alison, says even though "the girls find a little bit of satisfaction" in new episodes, all isn't roses in Rosewood, Penn.

"There's so much that they've been through and to know that Alison was alive and didn't do anything when certain things happen to them I think that they're going have to deal with that because that's painful, too. I think they're happy that she's alive and probably pissed off," laughed Pieterse in a recent interview.

Now that we know Alison is alive, Pieterse will play a more prominent role in episodes to come.

Pieterse says the big questions now are "where has she been hiding and who has she been hiding from."

Dead or alive, the 17-year-old South Africa-born actress is thrilled to be a part of such a popular series.

"TV is so fickle. We get 24 episodes a season. That doesn't happen as often anymore. It's a great blessing to be working nine months out of the year."

She recalls first auditioning to play the character of Hanna (the role went to Ashley Benson) and filming the pilot when she was just 12 years old.

Besides being a hit in the U.S., the show is also very popular internationally with fans in Brazil, France, the UK and the Philippines.

"It's funny to hear it in other languages," mused Pieterse.

For fans that can't wait to see how the series unfolds, Pieterse advises a great way to get answers is by re-watching old episodes.

"If you go back and watch again you'll pick up little pieces," she teased. "There are things to find."