A Santa Claus metahuman won’t be coming down the chimney during The Flash‘s Christmas-themed fall finale on Dec. 8 (The CW, 8/7c) — but there will most definitely be an intriguing new visitor on the scene.

At the moment, Joe doesn’t know that he has a son, but that will change when he and Iris meet Wally West (played by Dance Academy‘s Keiynan Lonsdale) during the pivotal installment.

The hour is “a lot about family, which is a big plot point for Iris this season, so that’s really exciting,” her portrayer Candice Patton shares. “It’s a good Christmas episode, just like the last one. Good villain, good love and good heart.”

Barry, meanwhile, is facing a turning point in his romance with girlfriend Patty. “Things are shifting with their relationship,” leading man Grant Gustin previews. While their courtship has been effortless thus far, the actor warns that it may be “getting a little harder.”

As the hero’s love life is possibly taking a turn for the worse, Caitlin’s may finally be looking up. She is, in fact, celebrating the holiday “with some mistletoe,” Danielle Panabaker teases with a laugh. Could Earth-Two’s Crimson Comet be the one locking lips with the fellow scientist? Panabaker hints that she has “some fun dialogue with Jay.”

Elsewhere, some of Central City’s most infamous Rogues — Mark Hamill’s Trickster, Wentworth Miller’s Captain Cold and Liam McIntyre’s Weather Wizard — make their returns, putting a damper on the festivities. With so many foes to battle, it’s a good thing the speedster has a new trick up his costume sleeve.

“Barry does another thing with his powers that he, in the moment, discovers and that he’s never done before,” Gustin teases. “It’s kind of goofy in a way where it’s very comic book-y. It’s cool.”