'Once Upon a Time,' ABC's fairy tale drama television series will return for its fifth season at 8:00 p.m on September 27 with some changes in its cast list. The upcoming season of the show will feature some new faces, though not all will have major roles.

According to IB Times, it has been reported that Merlin aka Sorcerer will play a major role in the upcoming sequel, since this character alone can save Emma Swan (Jennifer Morrison) from darkness.

While the producers are yet to reveal which actor will be portraying the character of Merlin, TV Line revealed that role may be played by a "Black Brit" in his 30s or 40s and having a "natural British accent." In addition, the website claimed that the character of Merlin may be very intelligent coupled with a "great wisdom."

Fans will also see another character joining the list. This new character is King Arthur, a resident of Camelot, who has been described as a great ruler and a "master manipulator" possessing the aptitude to "carry a grudge to the grave." In fact, the features of the actor who will portray this character may possibly have features similar to those of Merlin.

In the meantime, Queen Guinevere, Arthur's "eternal burning love," may also join 'Once Upon a Time' in Season 5. A Latino actress in her mid 20s and 30s is likely to portray the character of Queen Guinevere.

In addition, fans of 'Once Upon a Time' will also get an opportunity to watch Robin Hood (Sean Maguire) and Zelena aka Wicked Witch of the West (Rebecca Mader) as series regulars. A poll conducted by IB Times showed that Mader's character could steal the dagger from Captain Hook (Colin O'Donoghue) as a vengeance against Evil Queen Regina Mills (Lana Parrilla).

According to TV Line, Will Scarlet aka Knave of Hearts aka White King, portrayed by Michael Socha, will only appear as a guest star in 'Once Upon a Time' Season 5.