The Big Bang Theory Season 8 Episode 4
The Hook-Up Reverberation
Raj shows up at lunch with the guys and reminds them that he's going to introduce them to Emily the next night. Sheldon warns him that according to research he'll lose two friends due to his new serious relationship. The meeting goes well, except for with Penny. She feels that Emily doesn't like her.
Penny visits Emily to practice her sales pitch and finds out the truth about why Emily doesn't like her. Raj told her about his night with Penny. She tries to downplay the encounter, but Emily doesn't care. In attempt to fix the situation, Penny invites Raj and Emily over to her apartment. By the end of the night, they act as if they like each other, but really hate each other.
The guys decide they want to give Stuart the money he needs in order to open the comic book store. They talk to their significant others about the investment and get varying levels of support. It doesn't end up mattering because Howard's mother gave Stuart the money which infuriates Howard.