Penny tries to figure out what her feelings for Leonard are, since she is happy with their relationship, yet she is unsure if she is in love just yet. She confides in Bernadette and Amy about the matter, which results in Amy telling Sheldon about it. Sheldon, out of concern for Leonard and his hatred for changes, tries to talk Penny into maintaining her relationship with Leonard. Meanwhile, Raj finds a new friend in Stuart, to fill the void left by Howard, and Stuart gets accepted into their social group by Sheldon, so long as he behaves as Howard would. Howard meanwhile, gets bullied by his fellow astronauts.