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Madison Iseman on I Know What You Did Last Summer

Vital Thrills got a chance to speak with Madison Iseman about Amazon Studios and Sony Pictures Television series I Know What You Did Last Summer. The actress talked about playing twins in the show, the franchise it’s based on, and more.

Written and executive produced by Sara Goodman, the eight-episode series will be available exclusively on Amazon Prime Video Friday, October 15, in more than 240 territories and countries around the world.

Madison Iseman on I Know What You Did Last Summer

In the series, one year after the fatal car accident that haunted their graduation night, a group of teenagers find themselves bound together by a dark secret and stalked by a brutal killer.

As they try to piece together who is after them, they reveal the dark side of their seemingly perfect town – and themselves. Everyone is hiding something, and uncovering the wrong secret could be deadly.

The I Know What You Did Last Summer franchise is based on the Lois Duncan novel, which has a connection to the series. Madison Iseman said, “I haven’t read the book, though I feel like I have to because I’ve had so many people tell me how close our show is somewhat to the novel, of course, you know, I was a huge fan of the original movie from the ’90s. I didn’t see it when it came out because I was one, but maybe like 12 or 11.

“And then, of course, you know we rewatched all of them right before we started filming in January.” Because the cast filmed during the pandemic, however, Iseman said that this had to be done alone before they ended up in Hawaii, where the series is filmed.

Iseman, who has appeared in the Jumanji films, spoke about following in the footsteps of the cast of the original 1997 cult classic. “It’s awesome; it’s a lot of pressure. You know, we hope they love the show as much as we do,” she said.

“I think anytime you mess with people’s precious material and so many people love the film so much, myself included, there’s always going to be that level of like, are we doing enough… their blessing would probably be the greatest gift I think we could possibly get, as the cast and the creators of the show.

Turning a novel into a two-hour film is tough, and the series gives the writers more time to explore the characters. Iseman talked about the benefits of this story being a series. “You know our story is very character-driven,” she said. “It’s more than just about a bunch of teenagers running away from a mass murderer. It’s a story about a bunch of people who are all guilty and hiding something.

“So, when no one’s innocent and everything, something is revealed every single episode – we have much more time to tell that story, and so it’s almost like we give out little puzzle pieces, and then by the end, the audience can have the full picture, and then finally it all makes sense in the end.”

Madison Iseman

Press was shown the first four episodes of I Know What You Did Last Summer, and those episodes will be released all at once, with weekly episodes after that. We asked Madison Iseman about how much the mystery and action ramp up once things start going week by week.

“[We] got the first four episodes before we signed on. And we thought that was a lot, but you know, as we kept working, we would get more and more episodes… and I swear I did not realize how much bigger the story could get, and it does, it really does. We were holding bets over who we thought the killer was. I was wrong. We were all wrong except for one person.

“And it was a journey for us too, as the actors and the rest of the cast and crew, because we had no idea… it starts big, and it ends big.” She continued, “So by the end, I think Brianne (Tju) ran a Venn diagram. We were all trying to put together the pieces of who it possibly could be.”

Of the ending, Iseman said, “It’s a great payoff, you know. It’s not an ending that feels weak and unearned. It’s like the best treat possible. I’ll tell you that.”

Madison Iseman

Iseman said that she’s been a fan of the horror genre since she was a little girl. It’s a genre she’s worked in before with Annabelle Comes Home and Goosebumps 2: Haunted Halloween. She said, “I think I’ve always liked it because it’s a world with no rules, and I’ve always found the freedom in that as a creator. It’s just something I’ve always enjoyed. It’s also my favorite to watch so that probably says something.

“It’s just a fun ride from the beginning, but this project in particular, obviously the title, totally took me in when I first saw it in my inbox. I mean, I loved the movie when I was younger, but also, really, it was the opportunity to get to play twins because I think that’s on every actor’s bucket list. As soon as I read the pilot, my mind was blown.”

Madison Iseman plays twins Lennon and Alison. As she previously mentioned, it was a big opportunity for her. “I wanted to make them their own individual people,” she said, “but I did not want to make them your stereotypical twins you see all the time. So it was it was making them different but also finding some similarities and finding a way to ground them, which ultimately ended up being the death and suicide of their mother when they were younger.

“And just like how there was that sadness. Lennon, she’s the type of girl [that] demands attention when she walks in the room, and everyone loves her, and she just kind of keeps that part of herself hidden deep, deep, deep down until it just starts to eat her apart completely.

“Allison is the opposite, where she kind of wears her pain on her shoulder, you know, and that’s so apparent to see… to everyone else they’re so separate, but when they’re together, there’s something that happens that kind of bonds them together as sisters, as twins.

“In the end, there’s more to the story, obviously, that comes into play, but it was complicated. [I had] lots of preparation, lots of talks with our showrunner Sara Goodman just to make sure they were on the same page of where they wanted to be in the best way to tell the story.”