One of the consequences of Penny and Leonard breaking up is that Sheldon now has mixed allegiances. Leonard is his best friend and roommate, but he wants to remain friends with Penny if only because of all the work he's put into including her into his life. Sheldon goes to extreme lengths not to tell Leonard - or Howard or Raj for that matter - that he is having dinner with Penny. Will it be worth all the grief that he has to go through to keep this secret? Meanwhile, Leonard and Penny have to learn how to deal with the fact that they will still be seeing each other, and decide what form their new relationship will take.