Sheldon has been writing to the reclusive scientist Dr. Wolcott (Peter MacNicol) who invites Sheldon to visit him in his completely isolated mountain cabin. The women quickly ask Leonard, Raj and Howard to tag along with him, making this his bachelor party, despite Sheldon's assertions that it shouldn't be called such. Wolcott has a brilliant mind but his behavior is very strange to the guys. He tells Sheldon he cut off all contact with others to focus on science. Though Sheldon enjoys the science, he decides that he doesn't want to live like Wolcott because of his friends and Amy. The guys leave to avoid Wolcott, whose theories about time make him doubt whether the guys were ever there. Meanwhile, Penny and Bernadette throw Amy a quilting bee for her bachelorette party, which she quickly finds boring. When Amy tells them she wants a night full of bad decisions as she earlier implied, they go to a bar where Amy drinks a few shots and passes out in twelve minutes. When she wakes up back at the apartment hungover and disappointed, the women lie and reassure her she had a wild time, involving her drunkenly riverdancing.
Laura Spencer as Emily Sweeney (recurring seasons 7–8, 10, starring season 9): A dermatologist at Huntington Hospital. Emily went to Harvard and delights in the macabre and states that she likes her job because she can cut things with knives. Prior to meeting Raj, Emily was set up on a blind date with Howard. After finding Emily's online dating profile, Raj has Amy contact her as his wingman instead. Their relationship becomes exclusive, but Raj later breaks up with Emily when he becomes infatuated with the bartender Claire (Alessandra Torresani).
Sheldon and Amy are surprised to find that Wil Wheaton's new Professor Proton show is actually very entertaining and that Wil had Howard on as a guest. On Howard's suggestion, Sheldon apologizes to Wil, mending their friendship, and tells him he wants to be on the show; but Wil asks for Amy. Sheldon tells her to do it, but she says she often doesn't do things to avoid upsetting him. Sheldon is horrified when he realises how selfish he has been, especially when he finds out that the men do the same for him. Sheldon encourages Amy to go on the show to inspire girls to pursue science while trying to control his obvious jealousy for her. Meanwhile, Leonard writes a book about a physicist that solves a murder, the protagonist Logan Dean is based on himself. Bernadette points out Logan's mean boss Illsa is similar to Penny, who thinks it is based on Bernadette, though Leonard does not correct her. However, Bernadette tells Penny the truth, upsetting her and making her mad at Leonard. After calling his mother for advice, Leonard learns that Illsa is actually like her; but abandons the book when he realizes he wrote romantic tension into the relationship between the characters.