Amy: Could be anything. Bernadette: Well, let's just say the next time you move a dozen vials of raccoon virus to the fridge, make two trips. Howard: Guys, there was an accident at Bernie's lab. Howard: So I'm almost done writing the song for Bernadette. Howard: Well, tonight is the anniversary of our first date, and I wanted to celebrate it by writing a song for you. Howard: Yeah, but she's at the hospital in quarantine. I remember it was your favourite book growing up. I remember you saying how great it would be to have a first edition. I've got to find a way to stop this thing. Leonard: Hey, I get that you feel bad about all the attention, but still, what you did is amazing. Leonard: Holy crap, Sheldon, did you just figure out a method for synthesizing a new stable super-heavy element? Leonard: I will not. Leonard: Sheldon, that's incredible. Penny: It's a first edition of Hitchhiker's Guide to the Galaxy. Penny: What? Penny: What? Penny: Yes. Raj: Oh. Sheldon: That's the most romantic thing I've ever heard. Sheldon: This is the very copy of The Handbook of Chemistry and Physics in which I looked up the reaction rates of mendelevium and...
Amy: And what?
Plan: A: a new, stable superheavy element; Q: What does Sheldon calculate how to synthesize? A: his achievement; Q: What does Sheldon feel he ruined by his discovery? A: a fraud; Q: What does Sheldon feel after his discovery was erroneous? A: Amy; Q: Who tells Sheldon that he does not deserve the attention? A: Howard; Q: Who has everyone join him in performing a song he wrote for Bernadette? A: Bernadette; Q: Who is quarantined after an accident at her lab? A: their first date; Q: What anniversary does Howard want to commemorate with Bernadette? A: the hospital; Q: Where does Bernadette go to get a romantic song? A: Leonard; Q: Who says Penny never does anything romantic for him? A: Even Raj's advice; Q: What does Leonard say does not inspire Penny to be romantic? A: a first edition; Q: What edition of The Hitch Hiker's Guide to the Galaxy did Penny give Leonard? A: the gesture; Q: What does Leonard appreciate about Penny's gift? A: dozens; Q: How many mementos does Penny show Leonard? A: mementos; Q: What does Penny show Leonard that she keeps of Leonard's romantic gestures? A: his romantic gestures; Q: What does Penny show Leonard that she wishes she could do for him? Summary: Sheldon, unbeknownst to him, calculates how to synthesize a new, stable superheavy element, but then realizes that his discovery was erroneous, which spoils his achievement and makes him feel a fraud. His friends, co-workers and the scientific community praise him, but Sheldon just wants it to stop. Amy finally tells him he does not deserve the attention, for Sheldon the most romantic thing Amy could ever say. Howard has everyone join him in performing a song he wrote for Bernadette to commemorate the anniversary of their first date. However, Bernadette is quarantined after an accident at her lab so Howard and the gang sing the song for her at the hospital. Leonard says Penny never does anything romantic for him. Even Raj's advice fails to inspire her. Penny then gifts Leonard a first edition of "The Hitch Hiker's Guide to the Galaxy" - his favorite book growing up. Leonard appreciates the gesture but tells her that he already has a first edition of the same book. Penny feels bad and tells him she wishes she could be as romantic as he, showing him a box of dozens of mementos, examples of his romantic gestures during their time together. Leonard is moved, finding it incredibly romantic that Penny kept these things.