Use the situation around you like a prop. You need a topic, a thing, an action to start off of. Anything that you can use will be to your advantage to open. My friend opened 2 girls in a bar last week when they took a photo. He quickly jumped in and said, "ok, now one of the two of you, I'll take tour picture". They giggled like little schoolgirls and totally started talking to us for over 2 hrs. They ate that shyt up big time. And he was comin from the bathroom, he didn't plan it, he just attacked when the opportunity was there. If they of said "no thank you", that's that, walk away, nothing lost.
Try this approach. You'll have an 'in' and a topic.