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Draco Malfoy is coming to "The Flash" ... and the cast totally freaked out about it.

"Harry Potter" star Tom Felton joins the CW show as a series regular next season, playing crime scene investigator Julian Dorn. Little is known about the character, and the actor himself is still in the dark too!

"He's a CSI investigator, he speaks in an accent, at least so far," the Brit joked about the role at Comic-Con. "That's about it, but they told me there is a nice new piece of meat to sink my teeth into at some point in the season. I have no idea what that is."

Dorn is the product of Barry Allen totally screwing with the past during the Season 2 finale. When Barry went back in time and stopped his mother from being killed, it changed everything, and Season 3 plans to follow the comic's famous "Flashpoint" storyline.

"My character is introduced because of [Flashpoint]. For everyone else's existence, I've always been there. Barry's the only one who's like 'Who the hell is this guy?'" Felton adds. "Grant does this thing so well of making every situation slightly funny or finding lightheartedness in every scene. We've only done one scene, but it was a lot of fun."

The 28-year-old former child star says he wasn't very "knowledgable" about the series or comics before he joined the show, but caught a couple episodes while flipping through the channels.

"It's a really, really feel good show. I come up with crap metaphor that it's like watching 'Friends' and 'Spiderman' because it's a real action-based show with a lot of cool stuff, but it also makes you feel warm somehow and it's cozy," he adds. "I found it a very comforting show to watch, so to be part of it now is pretty awesome."

The cast is just as excited to have him around, as some of them are clearly Potterheads.

"How cool is it that he joined the show?" exclaims Jesse L. Martin. "We all kind of fanboyed out on him. We all tried to be really professional and cool, but man, as soon as he showed up, we were like 'Dude!'"

Martin adds that his character, Joe West, works with Dorn and has the "same sort of work relationship as me and Barry."

Uh oh, think Barry's going to get jealous?!

Some other tidbits we picked up from our talks with the cast:

  • Barry's old memories may go bye-bye. "He's the only one who knows the [original] timeline after he changes it, but his memories are being replaced from that timeline with new memories," Grant Gustin explains. "He has memories with parents that he never had. He has memories of graduating college and high school and them being there with him, but those memories are replacing stuff that he had with Joe, Iris, Caitlin and Cisco. When Barry starts to realize that, that's not ok with him and he has some regrets."

    According to Grant, "Flashpoint" itself won't last all season, but the fallout will..

    "He's going to try to put things back to the way they were, but that's probably going to be impossible," adds Gustin. "He's going to get some advice that's like, 'If you keep doing this, the world will implode. Please God stop.'"

  • There's a new Flash in town, as Wally West will be a speedster in Season 3.

    "It's very surreal," actor Keiynan Lonsdale says of putting on the suit. "I wanted to just go back in time and tell my 5-year-old self like, 'Yo, this is in your future by the way.'"

    Lonsdale says he has a higher appreciation for Gustin's work, now that he's suited up as well.

    "It's not restrictive, it's quite flexible, so you can move around in it, but it's still quite tight," he explains. "It's just getting used to moving in it, waking around in it and the mask is pretty tight, so you have to like figure out how too emote, so that took some getting used to, but it's fun."

    Expect to see Wally in costume in the first episode back.

  • Joe and his daughter may not see eye to eye. "I'm literally playing different aspects of Joe that I've never played before, because I always had different relationships with all of these different characters," Jesse L. Martin says of his "Flashpoint" alter-ego. "The idea of Joe and Iris having an absolutely contentious relationship is scary and fun for me at the same time. It keeps not only us on our toes, but it's going to keep our audience on their toes because they are not going to know what's coming next. We don't even know what's coming next!"

Find out when "The Flash" returns to The CW on October 4.