John Gallagher Jr. relived his formative years opposite Winona Ryder in “Gone in the Night”.

Gallagher Jr. and Ryder co-star in the new thriller movie from debutant director Eli Horowitz. The “Newsroom” and “Westworld” actor spent much of his youth watching Ryder and was floored to see that she lived up to his wildest expectations.

“She’s just incredible. I’ve been such a fan of hers since I was a kid,” Gallagher tells ET Canada. “I came of age in the ’90s and those movies were so important to me. Her filmography is, I think, one of the most illustrious and interesting of almost any actor in Hollywood that I can think of. That run from ’87 starting with, like, ‘Lucas’ and ‘Beetlejuice’, going all the way to ‘Girl Interrupted’. She’s had this incredible run. And now to be back in the limelight in such a way with ‘Stranger Things’.

“I was thrilled when I got the script because I found out that she was aware of my work and that she had kind of signed off on me being cast in this role. I couldn’t believe that she knew who I was. She’s just a dream. They say, Be careful when you meet your idols, because they somehow might let you down or disappoint you. I can really say that was not at all the case with Winona. She was everything I kind of dreamed that she would be and beyond. Such a sweet and tender soul, a real genuine artist, and a real kindhearted person. We just had a blast on set. I was like, ‘Tell me, please tell me more stories about working on “Dracula”. Tell me more stories about working with Tim Burton.’ I was a totally captive audience and she was kind enough to tell me some great tales about her life and her career.”

Gallagher’s fandom and proximity made him the perfect person to produce a Winona Ryder starter pack: three movies that give you a well-rounded sample of Ryder’s remarkable career.

READ MORE: Winona Ryder Talks ‘Stranger Things’, Her Breakup From Johnny Depp In The ’90s & More

“I would say ‘Heathers’. I think that’s such an arrival. She had already been making lots of films, but I feel like that’s an arrival into a next phase, a more adult phase of her career. She’s so good and so funny in that and it’s such a twisted and interesting satire,” Gallagher says. “I would definitely say ‘Reality Bites’. I think that’s such a fun film to watch all those performances. You’ve got blistering performances from her and Ethan Hawke and then young Janeane Garofalo and young Steve Zahn. It’s directed by Ben Stiller and his work is so impressive in it.

“And then the one that’s jumping out to me after that is ‘Edward Scissorhands’ because it’s just such a beautiful film and such a gothic, strange fairy tale and still such a moving love story. Oh, my God. ‘Hold me.’ ‘I can’t.’ Woah! When that line comes up at the end, that’s just a waterworks for me. That one always gets me, always makes me cry.”

As for his own career, Gallagher starred alongside Jeff Daniels, Emily Mortimer, Dev Patel, Olivia Munn, and more in “The Newsroom”. He chewed on what a reboot of “The Newsroom” might look like in 2022.

“We were right on this,” Gallagher says. “There was a changing of the guard at the time that that show aired. When you think about it, it started airing 10 years ago this summer, which is… I don’t know where the time went, but it was before streaming. It was really right before everything went through into the stratosphere with Twitter and social media and the idea of breaking news mostly coming from online outlets. If you did it now, I have no idea what it would look like or how it would seem.

READ MORE: Green Day’s Billie Joe Armstrong Reunited With Stolen 1962 Chevy

“I caught a clip of it recently online. I’m not slighting the show in any sense because I’m very proud of it, but it’s funny how dated it already seems with just a decade of time elapsing. Which I think just speaks to how fast things move these days. Technology is advancing and developing almost faster than we can get used to it. So if you were to do it now, I feel like it would be probably like a multimedia show. You’d watch part of it on TV and then you log into a streaming site and then you’d finish the episode on your phone or something. And then you log into your mental algorithm to see the season finale.”

Gallagher also played a key role in the Green Day Broadway production American Idiot. The actor and musician lived out every Green Day fan’s dream of rocking out with Billie Joe Armstrong and friends onstage.

“They have this side band called the Foxboro Hot Tubs. It’s kind of a side project. It’s kind of like a glorified bar band. They do a lot of covers and they play these garage songs that sound like the Kinks or the Sonics. They don’t play as much anymore as they used to but there is a stretch there where they would play tiny clubs,” Gallagher says. “I remember one night it was a Sunday night we were doing American Idiot on Broadway and they played a Sunday night show at this club, the Bowery Electric in New York City, which only holds a couple hundred people.

“They just crammed the place full of first come, first serve Green Day fans, and they played like a three-and-a-half-hour set. People were covered in beer. People were throwing keyboards, dousing themselves in Pabst Blue Ribbon. I got yanked up onstage to sing with Billie Joe a couple of times. I was stage diving. The end of the night gets a little fuzzy for me because I over-served myself. It was one of the most rock ‘n’ roll fun nights I think I’ve ever had. It all happened because Green Day was so generous with letting us into their social circle while we were doing that show.”

“Gone in the Night” premiered in theatres on July 15 and is headed to on-demand on Aug. 2.