Pretty Little Liars creator, Marlene King, has spoken about how production is going for Pretty Little Liars: The Perfectionists.

Speaking to ET (see below) about Sofia Carson's character, Ava, King said: "Sofia's character Ava has, in my opinion, one of my favorite [secrets]. Everybody has a secret going into this new show, and her secret is really one of my favorites. I don’t want to give up what it is, but it's pretty awesome and it's pretty cool and she's kind of a fierce badass - in her own Sofia way because Sofia is so adorable.

The writer and producer does not think it's necessary to binge-watch the cult teen drama Pretty Little Liars in preparation for this spin-off but added: "You don’t have to have watched Pretty Little Liars to enjoy The Perfectionists, but you'll find a lot of Easter eggs in the new show if you do. Just prepare for a fun new ride."

On the storyline for the mystery thriller, she revealed: "Well, I don’t want it to be a spoiler for people who haven’t read the books yet, but the books have a twist in them that would be kind of impossible to pull off on a TV show.

"So I think it was great inspiration for the show, but we kind of go off [book] a little bit sooner rather than later - unlike with PLL, which I think we were really true to the first four books."

Pretty Little Liars: The Perfectionists will be shot on location just outside Portland, Oregon as the books the story line is based on are set in the Pacific Northwest.