After Leonard tells Sheldon that he is having surgery to repair his deviated septum, Sheldon is convinced that Leonard will be the one in seven hundred thousand that will die from the anesthesia. Sheldon tries to convince Leonard of his early demise from this unnecessary surgery by reducing the odds through other factors. As such, Leonard has to figure out a way to get the procedure done without letting Sheldon know. Meanwhile, Raj tries to figure out what to get his parents for their fortieth wedding anniversary. An incident with the Koothrappalis makes Howard and Bernadette wonder if they will make it to their fortieth, and what they can do to strengthen their marriage.