Parenting dilemma. Husband and I disagree on what movies children can watch.?

My husband and I are both Christians. We are a combined family. I had 3 children when we married and he has 1. Our parenting styles are different. One of the areas we disagree on are the types of movies we let them watch. My stepson is used to watching pretty much anything he wants. He's only 10 years old. My children are censored. We disagree on what is appropriate for them. For example, today my stepson asked to watch Van Heilsing (vampire movie PG-13). I said no, it's demonic and not appropriate for anyone, not to mention a 10 year-old child. He told me my husband lets him watch it and he asked if he could watch it when my husband got home. I told him I would talk to him about it. I don't even want the movie in my house. My stepson is dealing with a lot of negativity at home and I can't see why my husband doesn't see that his movie choices are not helping him. In my opinion we should be flooding him with positive, uplifting and Christian/family movies. they like watching death, murder, destruction and witchcraft. It drives me insane. My stepson also tries to lure my 8 year-old daughter into watching violent stuff and perverted stuff on tv. He'll tell her to come here, rewind the movie, and show her a 1/2 naked man or a comment. My stepson knows that he can get between the two of us with this and he uses it often. We just flat out don't agree. I don't know how to deal with it. How do I knowingly let a child watch something I know is morally wrong when my husband says it's okay? Getting upset just allows the enemy to divide us. I feel his son tries to divide us on many issues and I don't think my husband sees it. This is not just a matter of opinion to me. This is something to me that is affecting his mind and spiritual condition.