By Jessica Michele Herring (staff@latinospost.com) | First Posted: Oct 09, 2013 10:35 AM EDT

It's almost time to go down the rabbit hole: ABC's "Once Upon a Time in Wonderland" is premiering on Thursday. 

The "Once Upon a Time" spinoff, which focuses on Alice and her journey in Wonderland, will have a new set of fairytale characters to enchant audiences. But on Thursday, viewers may see a couple of familiar faces. According to TVGuide, some "Once Upon a Time" characters will cross over into the "Wonderland" world. The premiere episode will feature two "Once" characters, and one of the characters is someone who fans have been yearning to see again. 

The spinoff series will also introduce new classic fairytale monsters as well as fairytale characters.

"Wonderland" will introduce mythical Scandinavian monster Grendel from "Beowulf" into the story, TVLine reports. In "Wonderland's" third episode, Grendel will go after Alice (Sophie Lowe) and the Knave of Hearts (Michael Socha), who are on a quest to seek the genie. Series co-creator Adam Horowitz said that Grendel is a "large, warted, ogre-like beast." Cannibalistic Grendel is going to pose a deadly threat to Alice and the Knave. However, as is true with most of the show's characters, there will be more to Grendel than viewers may expect. 

Aside from Grendel, Horowitz said that the show will not be delving deep into the Nordic legend. "It's a wink-and-a-nod, as opposed to a real deep-dive into 'Beowulf,'" Horowitz explained. 

The debut season of the series based on Lewis Carroll's seminal novel will focus on Alice, a girl living in Victorian London who believes in the fantastical world of Wonderland. Doctors diagnose her as insane, and try to cure her of her presumed mental disorder. Nevertheless, Alice believes in Wonderland, and is taken to the magical world by the White Rabbit just before the doctors giver her a treatment to wipe her memory clean.

Viewers will then be brought into Wonderland, complete with the White Rabbit, (voiced by John Lithgow), the hookah-smoking caterpillar (voiced by Iggy Pop) and the Red Queen (Emma Rigby). Everything isn't like the original, however--viewers will see some characters from the famous Arabian fairytale "Aladdin" thrown into the mix. One of main story lines in the show is the love story between Alice and the genie.

According to the Hollywood Reporter, Edward Kitsis, the show's other co-creator, shared who viewers will meet in Wonderland while at the TCA press tour. "You are going to meet Jafar (played by "Lost's" Naveen Andrews), get more of the Red Queen and get more a sense of that world."

Kitsis and Horowitz described the series as a "psychedelic romance."

"It is trippy. It is weird. It is intense," Kitsis said.

According to TV Line, it was also revealed that Barbara Hershey is planned to reprise her "Once" role as the Queen of Hearts in flashbacks. The Red Queen will have an "uneasy alliance" with Jafar, the famous villan from the Arabian tale. Both characters work to keep Alice from reuniting with the genie, Cyrus (Peter Gadiot).

Kitsis and Horowitz said that Jafar will certainly be a villain, as he is in "Aladdin," but he will also have more of a human side. "First off, like any character we introduce, we approach it from [asking] how do we humanize [the character], what's the way to make it real relatable and grounded, and then we find an awesome actor," Horowitz said.

"It's about two big things," Horowitz added. "What does he want? And how did he get the way he is in order to want that thing?"

"Once Upon a Time in Wonderland" premieres October 10 at 8 p.m. on ABC.