I'm going to a "Harry Potter and the Order of the Phoenix" black curtain screening. How early should I get there, to make sure that I can get in?

We're about to move into a new place and I've decided to decorated my husband's bathroom a black and white look. I just bought a vinyl shower curtain that's a soft white and has blocked black and gray boxes on it. It's really nice and trendy. But I don't know if I should go with black rugs and red bathroom accessories or just black rugs and accessories. I would like a touch of red in the bathroom but I don't know where to add it. I know how to decorate when I already have the items but I don't know how to pull different colors together to create a dramatic effect. Any advice would be appreciated it!!!!

I've looked everywhere i could think of and i haven't found one yet. I want pink with black or black with pink...Where can i find bathroom decorations with those colors?