For the first time, the Mikaelson clan will face off with their sire line of vampires when "The Originals" kicks off Season 3 on The CW this fall.

Last season, the Mikaelson siblings had an epic showdown with both of their parents and their all-powerful evil aunt. However, in the new season, they will find themselves going to battle with their own children, when The Trinity comes to New Orleans.

The Trinity consists of the first vampire Klaus (Joseph Morgan) ever sired, the first vampire Elijah (Daniel Gillies) ever sired, and the first vampire Rebekah (Claire Holt) ever sired. 

"We learned how to make vampires when my sire was created," Morgan told Entertainment Weekly. "There's definitely a bond there. We owe each other a lot."

Things will get especially complicated when Klaus meets his progeny, Lucien, played by actor Andrew Lees. Although Lucien's arrival will be reminiscent of an old friend coming to town, he actually won't be that happy to see Klaus, since he left him behind, along with almost every other vampire he turned, except for Marcel (Charles Michael Davis).

"There's also this element that it's not just the three of them but they're in contact with a lot of the sire line for each of us so it's like, 'Hey, remember us? All those vampires that you turned who you've now abandoned? Well guess what, we're not too happy about that and here's why,'" Morgan says. 

Lucien is described as a smart, charming man, who takes pride in his success and ability to stay two steps ahead of everyone else.

Executive producer Julie Plec also teased that viewers can expect to see extreme flashbacks when the show returns, which will show Klaus and Elijah in their early days as vampires.

"We have a whole series of flashbacks over the first chapter that tell the story of the Originals' first year as vampires before the word 'vampire' had even been assigned to them, and them learning what they were capable of, where they could fit in, how they could adopt the manners of a rich and cultured family even though they were tattered Vikings on the run," she told EW. "Within those flashbacks, we see the origin story of each of The Trinity, and we understand why The Trinity themselves might have reason to be a little pissed off at our hero family."

Fans can also look forward to seeing more of Holt as Rebekah in the flashbacks. 

"Right now we're trying to work with Claire's schedule and it's all working out nicely," executive producer Michael Narducci told E! News. "Claire is phenomenal and we love to have her on the show. We've got a whole flashback storyline that she will participate in, and then we have some ideas on how we might see Rebekah again in present day in both bodies. Not at the same time!"

In addition, Nathaniel Buzolic will reprise his role as Kol, while Casper Zafer is set to return as Finn's original body.

The new season of "The Originals" will premiere on The CW on Thursday, Oct. 8 at 9 p.m. EDT.