- California Doubling: Some of the scenes were actually filmed in Montreal, Canada.
- Fake American: Australian Rose Byrne as Alex. Averted with Lisa though as she mentions that her parents were foreign, implying that she just kept her accent from growing up with them. Although if you want to get technical, Lisa says her parents grew up in Prague - when Diane Kruger is German.
- The Other Marty: Paul Walker was cast as Matthew but had to drop out due to commitments to The Fast and the Furious.
- Playing Against Type: Rose Byrne is best known for playing hyper-competent Brainy Brunette types, or else playing such types for laughs in comedies. Here she's playing a manipulative Yandere.
- The Remake: This is an American remake of a French film called L'Appartement. The restaurant called Bellucci's is a Shout-Out to Monica Bellucci, who played the 'Lisa' character in the original.
- Those Two Actors: Diane Kruger and Rose Byrne had also starred together in Troy that same year, though they had no scenes together.
- What Could Have Been: Joel Schumacher was the original director, and Brendan Fraser would have starred as Matthew.
Trivia / Wicker Park