what do you do?

when point of view characters keep elbowing their way into your current novel, thus necessitating you working on threading them into backwards through the plot, instead of working toward the end of the plot, so that you actually know what happens then?

I started with two point of view characters, the hero and the heroine. This format has worked for me in several novels and I expected it to work for this one. Then the evil villain decided that he needed a few pages to explain what it is that ...