Sean Astin has been a familiar face to millions for more than 30 years, but his turn as Bob Newby on season two of “Stranger Things” took the “Goonies” and “Rudy” star to a new level of fame with the younger generation. In a show filled with interdimensional monsters and telekinetic preteens, Bob stood out as the everyman who stepped up in the biggest way when it mattered most.

Astin: “I attend a lot of regional Comic-Cons all over the world, and I started hearing about this show within days after it premiered. People would come up to me and tell me I had to see this show because it was ‘The Goonies,’ and it was the ’80s all over again, and how much it reminded them of the movies that were done then.

“I got an email from an agent saying, ‘There’s an audition for you for “Stranger Things” if you’re interested.” I looked at my wife and said, ‘Huh, that’s not a coincidence.’

“The first thing I did was binge the whole first season, which was brilliant, then I read the scenes. They wanted me to audition for the investigative reporter character, the conspiracy theorist character. And I loved that character and my kids helped me work on the scenes. So I did the audition and I really enjoyed it. I thought I did a good job. They called me when I got home and said they really liked it, but there’s another character they want you to come back in for. I thought, ‘OK, this show is a galactic success and they want to be very careful about what they’re doing so the least I can do is go back in and try to show them what they’re looking for.’

“It was very clear prepping Bob Newby that it was tailor-made for me. I remember one of the scenes was talking to Will in the car and trying to encourage him to stand up to the monster in his nightmares.

“Noah [Schnapp] was performing in the hospital bed when Will is sort of possessed by the monster [and] watching his absolute commitment to what he was doing seemed like something you would see in a very mature, adult performer. His just raw emotion really took me back.

“Winona [Ryder] and I knew each other, sort of grew up alongside each other in the industry. Then we did a little movie together like a decade ago. …Whenever we were on set together, there was just this warm, good, positive just enjoyment of being around each other. And I think it comes through on-screen too.

“For the first few episodes I was like, ‘Are you sure you wanna kill off Bob?’ … Because Bob came across so likable, I think they kept him around for a while. And I thanked them for letting him do something heroic. But I thought maybe he’d stop them from getting hit by a bus or something. I didn’t know he’d go totally Sigourney Weaver in ‘Aliens.’ I really enjoyed that drama and suspense in the end of that character’s storyline.

“Your job when you step onto a moving freight train is just not to do anything to derail it. So I was relieved that my inclusion in it was well-received.”