The reason I ask, Regin, is because you mention that these people are unbelievers. And praise God that you have been moved to reach out to them! We know that unbelievers need to hear the Gospel for it is the power of God unto salvation (Rom 1:16). But if you haven't seen it already, the Gospel is not presented in the Passion of the Christ. For this reason alone it would be ineffective. However, the greater problem, as others have repeated, is that the movie itself is an act of sin according to the Law of God. We would not show someone Christ by stealing or committing adultery, would we? In the same way, it profits no one to present Christ through a violation of the 2nd commandment.
But I am still curious if a language barrier is the reason you are selecting a movie. Not that this makes it right, but curious nonetheless. I know with some tribal cultures the Gospel is presented with an acting out or visible demonstration of the events surrounding the redemption of man. However, we need to be very careful about not overstepping the Law of God.
Regardless, just know that it is God alone that has the power to save these lost people. There is nothing Hollywood can do to make God's work more or less effective. If we trust in him alone and bring forth the Gospel as he has intended/commanded, God will bless our efforts according to his good will. If we disobey him, it is not as if God will always refuse to save the unbeliever (as if our piety is the tipping point), but should he do so and pluck them from darkness it would be in spite of our actions, not in blessing our actions.
It is likely that you have seen the movie since you wish to show it others. Perhaps it made an impact upon you and filled your soul with emotions that have inspired you to serve Christ. If this is the case, just know that these things are so, again, in spite of the intentions of the film. It was not pleasing to God for the movie to be made. But it is possible the he was pleased to use this in a positive way regardless of the sin behind it. Sometimes man will do something evil and God will use it for good (see Gen 50:20). I know this all too well myself, for when I discovered Christ I was a hedonistic sinner--and he used it all towards his glory. But upon being showed the truth of God, should we sin so that grace may abound? By no means. (Rom 6:1-2 ff)
Prayers are with you dear friend.