Sam wanted to grab something to eat before he went to see the play, and figured the common room would be the best place to look first. When he noticed that someone else was already there, Sam glanced over to see if it was someone he knew, and stopped in his tracks. The guy looked strangely familiar, and after a few more moments, Sam realized it was the guy from his weird dream. Staring might not have been appropriate, but it was all he could really do.