Leonard, Sheldon, Howard and Raj are all taking a train trip to San Francisco to attend a symposium, at where the scheduled keynote speaker is Nobel Prize winning physicist Dr. George Smoot. Leonard, Howard and Raj, who all wanted to travel by plane instead, change their mind about taking the train when they see on board the beautiful Summer Glau, who they recognize from her role in Terminator: The Sarah Connor Chronicles (2008). Howard and Raj argue about who between the two has the right to hit on her, Raj who would need to take a trip to the bar car first. Meanwhile, Sheldon has forgotten an electronic file at the apartment he deems important for Dr. Smoot. After Leonard talks him out of getting off the train to go back to retrieve it, Sheldon decides on the slightly less abhorrent option of telephoning Penny to email it to him, which would entail Penny entering his (gasp) bedroom.