Bernadette and Amy are attending a conference together. Despite being without their regular third, they end up not talking about science but boys like they would usually do with Penny. This discussion takes a bit of a turn that threatens the fun they were having. Raj is still pining over Lucy. As Raj can now at least talk to women, Howard suggests that he go to a graduate student mixer. Since Bernadette is away, Howard even offers to accompany him to be his wing man. At the mixer, Raj makes a connection with an unexpected person. And Penny and Sheldon both miss Leonard, although Sheldon does his best not to admit it. An impromptu telephone call to Leonard makes Penny reevaluate how she is feeling about Leonard being away. As such, the focus of Penny and Sheldon's time together turns from Leonard to each other.