Summer 3D was the planned 3D American Slasher Horror Film sequel to Last Summer 3D, I'll Always Know What You Did Last Summer, I Still Know What You Did Last Summer and I Know What You Did Last Summer.
It was to be written by Kevin Williamson in his return to the franchise and be directed by Jim Gillespie who had been the director of the first instalment in the summer franchise.
The film was scheduled for a July 4th, 2012 Release in all theaters
It was to be the direct sequel to Last Summer 3D picking up with the three unfortunate youths: Marla, Janine and Leo running over the partygoer from the previous summer believed to be Tamara Willis.
The Film was to star Freddie Highmore, Miranda Cosgrove, Geffri Maya, Sarah Hyland, Nicholas Purcell, Nicholas Hoult, Ashley Edner, Daveigh Chase, Jake Thomas, Jonathen Lipnicki, Daryl Sabara, Cassie Scerbo, Matthew Shively, Jennifer Lawrence, Aaron Johnson and Andrea Bowen.
- Freddie Highmore as Leonardo Hemlin
- Miranda Cosgrove as Marla Avenore
- Geffri Maya as Janina Llewis
- Jessica Barden as Katie Featherson/ Leader of the Popular Girl Clique. She is the biological daughter of Walter Nasley.
- Nicholas Purcell as Callum McAllister/ Boyfriend of Katie
- Nicholas Hoult as Rennie McAllister/ Brother of Callum who shares a crush on Marla
- Katerina Graham as Fiona Mortimer/ Member of the Popular Girl Clique and best friend of leader Katie. She is Marla's friend in the Popular Clique.
- Daveigh Chase as Nina Harmonez/ Member of the Popular Girl Clique who considers Fiona to be her best friend of Emma Tette and Nate Colbin. He has a secret crush on Emma and is obsessed with the Southport Fisherman killings going as far to spreading the word of the recent murders around school and has a supposed exact duplicate of the original hook. In truth the hook he bought is a simple fisherman's hook from Taiwan he purchased off Ebay
- Jake Thomas as Lance Evven/ Boyfriend of Wendelin
- Jonathen Lipnicki as Craig Narsson/ Former friend of Laker Stalk from when he lived in Southport and boyfriend of Fiona
- Daryl Sabara as Kevin Sionore/ Leader of the Legends of the Past club at Premium Ave High and former friend of
- Cassie Scerbo as Jessa-Lynn Parker/ Member of the Popular Girl Clique who is very unsmart education wise
- Matthew Shively as Reece Aiken/ Best friend of Craig
- Jennifer Lawrence as Caterina Munroe/ Best friend of Wendelin
- Aaron Johnson as Nate Colbin/ Second Cousin of Colby Patterson who shares an undying crush on Fiona. He is the best friend of Maria
- Andrea Bowen as Maria Markowitz/ Social Outcast pretty girl who once was Manic Depressive. She is the best friend of Nate who is enraged he has a crush on Fiona as she secretly likes Nate.
- Kay Panabaker as Emma Tette/ Girl who drived pass Marla, Leo and Janina
- Brian Cox as Walter Nasley (seen through flashback sequences and pictures in Katie Featherson's home)
- Melissa Peterman as Susanna Willis
- Scott Bairstow as Fisherman
- Jenette McCurdy as Carrie Kellas/ Neighbour of Marla in Colorado/ Former neighbour of Julie James and Ray Bronson