Adaptation Overdosed: While neither are official adaptations, the book's author Blanka Lipińska admitted to being heavily influenced by Fifty Shades of Grey... which itself in turn started life as Twilight fanfiction, before enough alterations were made to turn it into an original work. And then 365 Days got film adaptations, too.
Follow the Leader: The trilogy is influenced by Fifty Shades of Grey, a series of erotic romance novels involving BDSM and a domineering male love interest that became popular in the 2010s; the first two 365 Days novels were published the same year the film adaptation of Fifty Shades Freed was released. Blanka Lipińska was open about the fact the Fifty Shades series inspired her own writing.
Inspiration for the Work: Besides Fifty Shades of Grey, the author has stated that part of the inspiration for the book was taken from her own life, including an apparent kidnapping when she visited Sicily.
What Could Have Been: Blanka Lipińska said she considered writing a Perspective Flip told from Massimo's point-of-view but ultimately abandoned the idea, stating she wasn't interested in writing another book.
Write Who You Know: The author has stated that the character of Martin, Laura's self-absorbed Disposable Fiancé, was based on an ex-boyfriend of hers.
The film
Approval of God: Blanka Lipińska, the book's author, wholeheartedly gave her endorsement to the finished film, particularly praising the sex scenes.
Fake Nationality: Massimo's ex-girlfriend Anna, another Italian character, is played by Polish actress Natasza Urbańska.
Pop-Culture Urban Legends: The cast and crew of the film have repeatedly refuted the rumors that the actors were actually having sex during filming; while shot in an explicit manner, the sex scenes are all simulated.
Vindicated by Reruns: The film was first theatrically released in its native Poland, and it was a moderate success. Then it was released on Netflix, and became a worldwide hit.
What Could Have Been: For the airplane scene, the book's author Blanka Lipińska said that she offered to play the flight attendant herself, both because the scene had generated a lot of controversy already, and because she felt that only she "could show what the scene was truly about". However, the production company declined and an actress was hired to perform the scene.
