Math. Science. History. Its good Big Bang Theory didnt unravel all its mysteries.

When it was all over on Thursday night, and all the bazingas had been bazingad out, the CBS comedy wrapped up its 12 seasons and 279 episodes without the pomp and circumstance of so many TV finales before it. Like the takeout the group chows down on in the final shot of the series (as theyve done so many times before), it was satisfying while leaving just the right amount of leftovers, including one of the shows oldest questions: Whats Penny s (Kaley Cuoco) maiden name?

Ahead of the finale, Cuoco teased that an answer wouldnt be forthcoming, and she was into it.

I kind of love it, she told TVLine of the decision not to reveal the characters last name.

True to her word, in one of the last moments of the series, while Sheldon (Jim Parsons) accepts the Nobel prize in physics and tosses aside his previous, self-indulgent speech to instead thank this friends, he called Penny by her married name, Penny Hofstadter, thus sealing away the mystery for good.

Like Cuoco said, the show tied up plenty of other loose ends along its two-part finale: As mentioned, Sheldon (Jim Parsons ) and Amy (Mayim Bialik ) win the Nobel prize. Penny and Leonard (Johnny Galecki) also decide to finally have a baby, and the elevator, which has been out of commission since the Big Bang debut in 2007, is even back up and running.

But Pennys last name was a gag Big Bang had no intention of spoiling. Over and over on the show, the other characters are constantly introduced by their whole names Dr. Sheldon Cooper, Dr. Beverly Hofstadter (Christine Baranski), etc. while Penny, the perennial foil to everyone elses information overload, has pretty much just been Penny.