At the end of season 2, the Original siblings faced their murderous parents and a crazy aunt. Season 3 promises more upheaval when the Trinity - the first vampires created by Klaus, Elijah, and Rebekah - appear in New Orleans.

"One of the stories that we're telling is that first 10 years of being a vampire after [the Originals] fled their raging father and their mother, and how they became the cultured, posh, fascinating people that they are today," Julie Plec, showrunner, shared.

"And that's how we introduce the Trinity: through that flashback storyline."

The flashback story also opens the door for Claire Holt's welcome comeback.

"We'll actually be seeing quite a lot of Claire in the beginning of the season in flashbacks. We'll see which of the three she sired and how that all went down and then we will come find [Rebekah] in present day, where she realizes she's in as much danger from the other sire lines as her brothers are."

The Trinity (Rebecca Breeds, Oliver Ackland, and Andrew Lees) will not unite the Original siblings, their presence will just drive the stakes between the siblings even deeper.

With Elijah and Klaus already at loggerheads, this new development could sunder blood ties completely.

"With Elijah and Klaus already being a bit frayed in their relationship, there is room for these new people to try to get in between them," according to Plec.

The Trinity's arrival has tipped many other boats. Because of her close ties with Klaus, Cami might be a target, according to Plec.

"Because Cami always has Klaus' eye, when Klaus' sired vampire Lucien comes to town, he finds Cami to be a VERY interesting element into how he can either get closer to Klaus or manipulate Klaus."

Marcel could also be affected:

"Because Marcel is this very dynamic leader of the vampire culture in New Orleans, he captures the eye of the Trinity who look at him as perhaps a potential ally," Plec shares.

Davina, now the New Orleans witches regent, also hones in on the Mikaelson family.

"Davina 100 percent hates the Mikaelsons and has made this rule as we get to the top of the season where no witch in town is allowed to help a Mikaelson with anything."

This move might backfire, however, Plec teases,

"But Davina is very quickly going to step in it a little bit ... It's hard to call for favors when you've been denying everybody theirs."

The Originals airs 9 p.m. ET on Thursday, Oct. 8 on The CW.