The Fortification Implementation
Season 8, Episode 20 - Aired April 9, 2015

When Sheldon feels down about being left out of a physics symposium, Amy suggests they spend their date night building a fort. Meanwhile, after Howard gets the title deed to his mother's old house, he is surprised when an unknown relative turns up on his doorstep. Meanwhile, when Penny appears on Wil Wheaton's podcast, she and Leonard have a big on-air fight.