Penny embarks on a new romance. In a drunken moment Matt and Lindsay find themselves in a compromising situation. The two spend the rest of the week avoiding their feelings for one another. After hearing that the human pupils dilate when looking at someone you love, Brian and Kurt try it out with everyone. It only proves successful however, when they look at each other. Meanwhile, Clare discovers Bob's secret ‘weapon' and has sex with him on her porch.