Sarah can get used to most of Sherlock’s weird habits – except his tendency to datecrash her and John. After he “accidentally” ends up at the same place as them three times in a row, she asks John for Sherlock’s number and texts him to meet up alone.
“What are you trying to do?”
Even if Sherlock were able to answer, he wouldn’t have to. His eyes tell the story.
“I’m not trying to take him away from you. Promise you’ll do the same.”
Her smile opens up a whole new possibility which Sherlock had not taken into account until now.