Bernadette discovers that Howard expects her to move in with him (and his mother) after their marriage. When she protests, Howard suggests that she move in to try it for a week. Things do not go well, as it continues to be evident how coddled Howard is by his mother.
Meanwhile, Leonard is convinced to escort Amy to a wedding. Though distracted by thoughts of Priya, Amy is finally able to pull him out onto the dancefloor to actually enjoy himself ... despite a Hokey Pokey mishap that results in a pulled groin muscle. At the end of the evening, Leonard makes it clear that Amy is "Not for you!"
This Episode's Science
Penny: You're a brain scientist. Can you explain to me why a brilliant man likes playing with toy trains?
Amy: Not without cutting his head open, no.