Hathaway is currently busy working on Christopher Nolan's sci-fi film "Interstellar" and its production will overlap "Laggies" schedule, making her unable to commit to the project.
Knightley will star in the movie that revolves around a young woman who reacts badly to her boyfriend's marriage proposal. She tells him she is off on a business retreat, but instead hides out with her new friend, 16-year-old Annika, reported Contactmusic.
"Laggies" has been written by Andrea Seigel and will be directed by "Your Sister's Sister" helmer Lynn Shelton.