* ActingForTwo: Several actors play counterpart characters from the different dimensions; Jet Li plays both protagonist and antagonist, plus a few additional ones that we see getting killed off. Each character is significantly different from the other; Creator/CarlaGugino plays Gabe's loving wife and Yulaw's rather trampy-looking consort. [[spoiler: She also plays his wife's BackupTwin in another universe.]]
* FakeAmerican: This film was early in Statham's career, so this was the first time the Englishman had been called upon to be an American. [[AccentuateTheNegative His accent is better in future films]].
* UnintentionalPeriodPiece: The soundtrack to the movie is ''very'' early 2000's, with songs such as [[Music/DrowningPool Bodies]] and [[Music/{{Disturbed}} Down with the Sickness]].
* WhatCouldHaveBeen: Originally, the film was supposed to star [[Wrestling/DwayneJohnson The Rock]] as the main character, but he chose to do ''Film/TheScorpionKing'' instead. Imagine two doubles giving each other the "eyebrow".
** Creator/JackieChan was approached for the project but turned it down because of his policy of never playing the bad guy.