The Big Bang Theory - 5x13 - The Recombination Hypothesis 2012-01-19 Comedy / Romance Jim Parsons - Sheldon Cooper , Johnny Galecki - Leonard Hofstadter , Kaley Cuoco - Penny Leonard, who broke up with Priya, asks Penny out to a spur-of the-moment romantic dinner for two, and the duo contemplates resuming their relationship. 25 TV-14