Leonard is aghast to find out a secret of Penny's: she believes in psychics. Meanwhile, Sheldon tries to assist Koothrappali in picking up a girl at a university mixer.
Amy and Sheldon's relationship takes a surprising turn during a game of 'Dungeons & Dragons'. Lucy and Koothrappali have an awkward date.
The BAU is called to search for a man who is targeting children when an eight-year-old is found murdered on the Appalachian Trail.
After an explosion rips through a small town school, the team must track down the bomber before another attack occurs.
Randall adjusts to the foster system, Kate and Toby take the next step in their relationship, Kevin visits Sophie in New York, and Jack and Rebecca finalise Randall's adoption.
