Mike Flanagan Wrote a Script for an ‘I Know What You Did Last Summer’ Sequel Featuring a Shocking Courtroom Twist-Ending
“The entire thing in our minds was designed around a really cool trick ending that got us really excited.”

Next Friday, July 18, a new I Know What You Did Last Summer movie hits theaters. Freddie Prinze Jr. and Jennifer Love Hewitt will return as Ray Bronson and Julie James and the plot will see a new group of young friends stalked by a killer 27 years after the events of the original. The movie will be directed by Jennifer Kaytin Robinson, who also co-wrote the story and pitched the reboot to Sony. However, horror fans will be interested in a completely different I Know What You Did sequel that could have been — with major behind-the-scenes talent attached.
Around 2014 an I Know What You Did Last Summer remake was considered and a script was written by Mike Flanagan and Jeff Howard. The two have made horror hits like The Haunting of Hill House and Midnight Mass together. The script would not be based on Lois Duncan’s book or the previous I Know characters.
The movie would have taken place in Antigua where a group of American friends are celebrating the end of high school. Drugs cause one of the friends to hallucinate and he comes to in a police station where he is being questioned for the disappearance of a local woman he had been partying with. The trial becomes a media circus and although eventually freed, all the friends are stalked by infamy and warnings that someone “knows what they did last summer”. They hoped Jennifer Love Hewitt would have had an extended cameo as the producer of one character’s true crime podcast.
The entire thing in our minds was designed around a really cool trick ending that got us really excited. Like a real, Witness for the Prosecution-style nod of an ending where something comes in and blows things up in a way that – you could’ve seen it all along, but you never would have seen it. That kinda deal. It was just so much fun, but it was a big controversial ending from the very moment of the pitch. Literally, I think 99% of the interest from me and Mike was that ending. It was really cool to us.
Jeff Howard, on his unmade I Know What You Did Last Summer remake
If you’re unfamiliar with film Howard was inspired by, Witness for the Prosecution (1957) is a courtroom drama about a man accused of murdering a wealthy widow for her inheritance. During the trial, the man’s cold-hearted wife testifies against him, claiming he confessed to the murder. However, he is found not guilty as the jury believes his wife and her lover conspired to frame him.

The movie is famous for its twist-ending which reveals (spoiler alert) that the wife only pretended to be cold-hearted. As she was told the jury would not find an alibi given by a loving wife believable, she fabricated the affair as a ruse to secure an acquittal. When her freed husband gloats and announces his plans to leave her, the wife stabs him. As the credits roll, audiences were asked to keep the movie’s big twist a secret, with a voiceover saying: “The management of this theater suggests that, for the greater entertainment of your friends who have not yet seen the picture, you will not divulge to anyone the secret of the ending of Witness for the Prosecution.”
Unfortunately, Flanagan and Howard’s script never made it to production and the sequel was scrapped. However, since it is not attached to any existing characters or timelines, perhaps we’ll see this I Know What You Did sequel made if this summer’s reboot is a success. We’re looking forward to seeing I Know What You Did Last Summer in theaters on July 18, we just wish we’d have gotten to see the 2014 version too.
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