Among the cast of the newly minted version of slasher thriller “I Know What You Did Last Summer” are Jennifer Love Hewitt and Freddie Prinze, Jr., veterans from the 1997 original.

Also, as a mysterious new figure this installment: Billy Campbell, 66, whose credits go back to the ‘90s with “The Rocketeer” and “Bram Stoker’s Dracula.”

“I’m not playing a lead role,” Campbell explained in a phone interview from Norway where he lives with his Norwegian wife and two children. “I am the father of one of the protagonists.

“I’m not sure what else I can say, without giving anything away. I guess that’s the fun of these movies. And actually, I’m more or less kept in the dark — and I was very happy for it to be that way.

“I mean, when I first got sent anything, it was just a couple of scenes involving my character (and I still don’t know some things).

“I must confess, I haven’t seen any of the others” — this is the fifth film in the franchise — “which are all kind of funny and gory at the same time. I can say that the script achieved that.

“But in my career I like having a good time. And I like my job because I get to go to different places and meet different people. This meant I got to spend almost four glorious weeks in Australia and another 10 days in LA earlier this year.”

Fittingly for a murder mystery, despite its imminent arrival, Campbell remains clueless about how it all wraps up. That’s because, he revealed, “several endings were filmed and nobody in the cast ever really knew, or maybe even today knows, who actually did it.

“I’m being very cagey because I do not exclude myself from having done it.”

When you’ve been making movies for far longer than many of your castmates have been alive, do they know who he is?

“Some do. They were so sweet. Chase Sui Wonders, who is theoretically the star of this movie, was a big ‘O.C.’ fan, and she said something right away.

“Actually, Freddie was also hugely sweet. The first day we met and worked together, he walked up, shook my hand and said, ‘When I was a kid and I was in Mexico and I was watching TV, I saw ‘The Rocketeer.’ And it made me want to be an actor.’

“So yes, a couple of them did know who I am or what I’ve done. And a few of the others, I think had no idea. Which I guess is the way the world is.

“Anyway,” he added knowingly, “you’re not what you’ve done.”