Marvel's new First Family is about to face a very, very old threat in The Fantastic Four: First Steps. The latest MCU movie introduces Pedro Pascal (Reed Richards/Mister Fantastic), Vanessa Kirby (Sue Storm/Invisible Woman), Joseph Quinn (Johnny Storm/Human Torch), and Ebon Moss-Bachrach (Ben Grimm/the Thing) as the new version of the Fantastic Four. But this isn't an origin story for the superhero foursome — they've already got their powers and have been saving the day long before the film begins. And that's a good thing, since rookies would be no match for the villains they'll soon be up against: Galactus (Ralph Ineson) and his herald, the Silver Surfer (Julia Garner). Who are these two big bads? They both previously appeared onscreen in 2007's Fantastic Four: Rise of the Silver Surfer, but director Matt Shakman's version promises to be more comic-accurate this time around. (If you don't want to know anything about the characters' comic book history in fear of potential movie spoilers, turn away now.) First introduced in 1966, Galactus was created by Stan Lee and Jack Kirby as a giant, cosmic entity that consumes planets to survive. The character was previously portrayed in Rise of the Silver Surfer as a big, amorphous cloud in space, but Ineson will portray the space god as he's depicted in the comics: a massive being in purple-and-blue armor. But while he appears humanoid in shape, the actor tells Entertainment Weekly that he's "not human in any sense." "He's a cosmic force," Ineson says. "He's so far developed after 14 billion years of existing that he's so far away from humanity. It was an interesting challenge to try and get your head around a being that wields that much power, but wields it without malice. He just does what he does." The actor appreciated the direction he received from Shakman in the beginning, which helped him unpack the long and complex history of Galactus. "Matt Shakman's description of him as a 14-billion-year-old cosmic vampire kind of says it all, with a horrific edge to it," Ineson says. "And the fact that at 14 billion years old, he is older than anything in the whole cosmos. He's lived through two big bangs." But Ineson had another, more personal tutor when it came to understanding Galactus: his own son. "I knew a little bit about it, but I'm blessed with a 25-year-old son who's a Marvel fan and always has been, so I've been living the Marvel universe through him for the last few years," Ineson says. "He really knows his stuff, so when I got the job, he turned into this Victorian schoolmaster, put me in MCU bootcamp for a month, watching many movies and everything that was relevant to Galactus and all this, and taking me through various storylines in the comics. [He was] an amazing teacher." Galactus is aided by his shiny, chrome herald, the Silver Surfer. Previously seen onscreen in the 2007 movie, played by Doug Jones and voiced by Laurence Fishburne, is the male version of the character, Norrin Radd. Now, Ozark star Garner is playing the first-ever live-action version of Shalla-Bal. In the comics, Norrin and Shalla-Bal are lovers from the planet Zenn-La. When Galactus threatened to devour their planet, Norrin agreed to become his herald and find other planets for him to eat. In return, Galactus promised to spare Zenn-La, saving Shalla-Bal. However, they are never able to rekindle their romance, as Shalla-Bal became empress of Zenn-La in Norrin's long absence. In an alternate universe, Shalla-Bal becomes the Silver Surfer herald for Galactus instead. "As soon as the opportunity was given to me, it was so exciting," Garner says of portraying the first live-action version of Shalla-Bal. "Her story's quite tragic, so that's interesting already, and visually it's interesting too. There was just a bunch of things to dig deep into. And also the fact that, because this was never told on screen before, it was a great opportunity. But there's definitely pressure entering the Marvel universe and this responsibility because of fans — like [Ralph's] son — but I had a lot of fun with it." Want more movie news? Sign up for Entertainment Weekly's free newsletter to get the latest trailers, celebrity interviews, film reviews, and more. While Garner isn't able to reveal what comics her arc is based on, she teased that "there's this mystery about her" that is intriguing. "There's this sense of this ambiguous energy going on of whether she's good or not," Garner says. "She is the herald of Galactus, so she works for Galactus, but you're not sure where she stands. Does she stand with her boss, or is she just doing what she's told? She has this mysterious energy about her, and slowly that mystery will get solved with the audience throughout watching it." The Fantastic Four: First Steps flies into theaters on July 25. —Additional reporting by Mike Miller