Dolph Lundgren had turned down Uwe Boll's offer once, before he eventually agreed on the advice of associate producer Bob Van Ronkel who had introduced them during a festival in Kazakhstan. Lundgren said in an interview to Empire magazine: "It was an experience, it wasn't exactly my taste, but I did it for other reasons. I was getting divorced at the time and I needed some cash quickly to pay for a few things... lawyers."
Dolph Lundgren injured himself on the first day of filming, making it harder for him to run and do the fight scenes.
Uwe Boll considered offering the role of Granger to Randy Couture or Steve Austin if Dolph Lundgren didn't accept (and he did turn it down first, before taking the job when he got divorced).
You can see Dolph Lundgren's name in Japanese which embroidered in the black-sash (kuro-obi) when granger teaches karate to kids at the beginning of scene in this movie.
This is the second time that Natassia Malthe replaced Kristanna Loken's movie role. The first time was in the BloodRayne sequels.