TV I Know What You Did Last Summer I Know What You Did Last Summer 6.4/10 by 226 users In a sun-soaked Hawaiian town with a mysterious past, a group of friends is left with a dark secret after a tragic accident. One year later, a member of the group receives a threatening message, and the friends now know that someone intends to make them pay for last summer. Details Casts Posters Images Title I Know What You Did Last Summer Alternative Titles First Air Date 2021-10-14 Last Air Date 2021-11-11 Number of Episodes 8 Number of Seasons 1 Genres Mystery, Drama, Networks Prime Video, Casts Madison Iseman, Bill Heck, Brianne Tju, Zeke Goodman, Ashley Moore, Fiona Rene, Cassie Beck, Brooke Bloom Plot Keywords , Lennon / Alison Madison Iseman Bruce Bill Heck Margot Brianne Tju Dylan Zeke Goodman Riley Ashley Moore Lyla Fiona Rene Courtney Cassie Beck Clara Brooke Bloom