What do you do when your doorbell rings at 10:21 at night?

So my hubby and I are sans kids for the night. It’s just the two of us spending some much needed alone time home. The doorbell rings at 10:21. Now, let me tell you that anyone who knows us knows not to ring out bell, because Max the killer attack dog (he’s a big German shepherd who really wouldn’t hurt anyone) will lose his mind. So the bell rings, Max starts to freak and I decide to answer the door. Max comes with me, and when we look outside, it’s two boys looking for my 15-year-old daughter. I asked who they were and why they were at my house at 10:21 (after Max stopped with his very intimidating bark). They said they were looking for my daughter. Then my husband comes out and says, very straight forward (with Max settled down), “Do me a favor and don’t come looking for (child’s name) here again. Call her or text her, hit her up on MySpace, but don’t come here again.”
I don’t know what scared them worse, the dog or the man.
It was effective, but I guess what I’m wondering is how would you deal with this situation?