I Know What You Did Last Summer cast and character guide: Who’s returning, who’s new, and who’s playing what

I Know What You Did Last Summer is scheduled to release on July 18, 2025, in the United States. The film premiered at the United Theater on Broadway in Los Angeles on July 14, 2025.

Owned by Sony Pictures Entertainment it is the fourth instalment in the American horror media franchise. I Know What You Did Last Summer, the film is a sequel to I Still Know What You Did Last Summer (1998) and features an ensemble cast with characters returning from the franchise’ 1997 film I Know What You Did Last Summer. It features Freddie Prinze Jr. and Jennifer Love Hewitt as the returning cast, reprising their previous roles in the franchise alongside Madelyn Cline, Chase Sui Wonders, Jonah Hauer-King, Tyriq Withers, and Sarah Pidgeon.

The movie follows a group of teens who reunite a year after trying to hide a deadly accident. Soon, they start getting threatening texts, as fear and suspicion take over. As someone targets them one by one, they must face their guilt and uncover who knows their secret—before it’s too late. Their friendship, trust, and lives are all at risk.

I Know What You Did Last Summer main cast

Given below is a list of all the cast and the characters in I Know What You Did Last Summer.

1) Jennifer Love Hewitt as Julie James

Jennifer Love Hewitt reprises her role as Julie James from the previous films of the franchise. Julie James is one of the survivors of the 1997 Southport massacre, a horror that occurred in I Know What You Did Last Summer (1997).

Julie is a strong, compassionate woman who overcame a traumatic experience in her life. Despite her intense shame, she works to prevent others from making the same errors. In the film, she comes back stronger and wiser, assisting the younger generation in facing the threat she once escaped.

Where you’ve seen her: Hewitt gained notoriety as Sarah Reeves in Fox’s Party of Five (1995-1999). She is widely popular for her character as Julie James in the I Know What You Did Last Summer horror media franchise.

2) Freddie Prinze Jr. as Ray Bronson

Freddie Prinze Jr. also returns for his role as Ray Bronson, Julie’s long-time partner, and a fellow survivor of the 1997 Southport massacre which occured in I Know What You Did Last Summer (1997). A modest and devoted man, Ray Bronson experienced a horrible tragedy alongside Julie years ago. He still bears the scars from their past, yet he loves her deeply. He supports Julie throughout the movie, applying his knowledge to help keep the new group safe.

Where you’ve seen him: Prinze Jr. has appeared in the first two films of the I Know What You Did Last Summer franchise. The actor is also popular for his roles in Scooby-Doo (2002) and Scooby-Doo 2: Monsters Unleashed (2004).

3) Madelyn Cline as Danica Richards

Madelyn Cline plays one of the main protagonists, Danica Richards, one of five friends who is being hunted by the Fisherman. Richards is the unofficial leader of the group. She has a key to solving the mystery and is central to the accident. Everyone is affected by her choices, and her guilt emerges as a central theme in the plot of the film.

Where you’ve seen her: Cline is popular for her appearances in Netflix’s Outer Banks (2020–present) and in the film Glass Onion: A Knives Out Mystery (2022).

4) Chase Sui Wonders as Ava Brucks

Chase Sui Wonders portrays one of the main protagonists, Ava Brucks, a close friend of Danica. She plays the emotional mirror of the group, adding complexity and drama with her breakdowns, suspicions, and loyalties. She stands in for the group’s emotional toll.

Where you’ve seen her: Wonders is known for her roles in HBO Max’s series Generation (2021), in the film Bodies Bodies Bodies (2022) and Apple TV+ satirical comedy series The Studio (2025).

5) Jonah Hauer-King as Milo Griffin

Jonah Hauer-King plays Milo Griffin, one of the protagonists and one of the group of five friends being haunted by the Fisherman. Milo is the logical problem-solver and thinker within the group. When something goes wrong, he frequently tries to take control and comfort people. Though he is still predisposed to terror, his position brings balance and logic.

Where you’ve seen him: Jonah is popular for his performance in Disney’s musical fantasy film The Little Mermaid (2023). The actor has also appeared in series such as Little Women (2017), Howards End (2017), World on Fire (2019–2023), and Doctor Who (2025).

6) Tyriq Withers as Teddy Spencer

Tyriq Withers portrays Teddy Spencer, a bold protector and the hothead of the group. Tyriq expects action and frequently engages in conflict with people because of his impulsiveness. His involvement raises risk, tension, and energy among the group.

Where you’ve seen him: Withers began his acting career in the CW’s television series Legacies, and later appeared in Tell Me Lies and The Game.

7) Sarah Pidgeon as Stevie Ward

Sarah Pidgeon plays Stevie Ward, the quiet observer of the group. Stevie goes from providing background assistance to becoming essential to the group’s survival. She is the quiet observer who slowly emerges as a strong voice as the narrative progresses.

Where you’ve seen her: Sarah has appeared in series such as The Wilds (2020–2022) and Tiny Beautiful Things (2023). The actress debuted on Broadway in David Adjmi’s play Stereophonic (2024).

Supporting cast of I Know What You Did Last Summer

Here is the complete list of the supporting cast and characters in the upcoming film I Know What You Did Last Summer:

• Billy Campbell as Grant Spencer
• Gabbriette as Tyler(as Gabbriette Bechtel)
• Austin Nichols as Pastor Judah
• Joshua Orpin as Wyatt
• Georgia Flood as Hannah Decker
• Nick Farnell as Chief Roberts
• Nick Hardcastle as Neal
• Simone Annan as Jill Spencer
• Luke Van Os as Officer Johnson
• Isaiah Mustafa as Andrew
• Leah McKendrick as Newscaster
• Todd Giebenhain as Jason
• Brian Duffy as Groundskeeper
• Dalia Rooni as Courtney

I Know What You Did Last Summer is set to hit the theatres on July 18, 2025. Stay tuned for more updates.