Sam noticed her friend was checking out the room, no doubt trying to work out who the most interesting people were to talk to, she had a knack for that. While Sam herself was trying to relax and not succeeding very well. It wasn't that she was particularly awkward in social situations but she was far from comfortable at a party where she knew nobody, apart from Lizzie of course.
Upon hearing the question she followed her friends gaze, "No idea" she replied, "Looks like he's checking out the crowd as much as you though" she teased taking a sip of her champagne.