- Actor Allusion: Adam Brody is wearing a Fight Club T-shirt while being interrogated by Brad Pitt. Presumably, Tyler Durden was played by somebody else in this universe. John's yellow/orange sunglasses later in the movie are also suspiciously similar to a pair seen on Tyler Durden.
- Deleted Role:
- Estella Warren planned to make a big comeback with a supporting role, but her part - she and Adam Brody play a husband and wife who get wrapped up in the film's plot - was deleted from the final print (although Brody remains in the movie).
- Keith David and Angela Bassett were cast as the bosses of the title characters, but only their voices remained in the final movie. David can still be briefly be seen in the reflection of a computer monitor during one single scene.
- Terence Stamp and Jacqueline Bisset also appeared in a subplot as terrorists that got cut.
- Missing Trailer Scene: Due to over an hour of scenes being cut before release, the trailers were filled with these. Every scene with Keith David and additional scenes with Vince Vaughn are gone.
- Real-Life Relative: Not at this stage but soon afterwards, the romance between Brad Pitt and Angelina Jolie was already well publicized before the movie came out, to the point that some initially assumed that this was a Gigli-style attempt at capitalizing on their romance. Apparently, they fell in love on the set.
- Recycled: The Series: There was an attempt to adapt the film into a TV series that never materialized.
- Romance on the Set: Brad Pitt infamously started a romance with Angelina Jolie while filming (he was married to Jennifer Aniston at the time, and eventually divorced her to marry Jolie).
- Throw It In!:
John: Nononononono! Accident!
- When Jane is going to her first shown kill, she correctly answers a question from ''Jeopardy!'. This was unscripted and spur of the moment on the part of Angelina Jolie.
- The scene where John accidentally shoots through Jane's windshield was supposed to have him hopping over the last fence, but Brad Pitt actually tripped and broke the fence. However, his muttered line of "Oh, dear God!" as he rushed through the mangled fence was so amusing that the director kept the scene the way it was.
- What Could Have Been: Brad and Angelina were both replacements when filming began to snarl. Before the two of them were confirmed, others such as Will Smith, Johnny Depp, Cate Blanchett, Nicole Kidman, Catherine Zeta-Jones, Eva Green and Gwen Stefani, were considered. Now try to imagine both A) the movie with any combination of the previous actors, and B) a world without over a decade of Brangelina.
Trivia / Mr. & Mrs. Smith (2005)