Aired Saturday April 13, 5:40pm - 6:10pmon E4

The Big Bang Theory

Series 9 Episode 18: The Application Deterioration

Leonard, Sheldon and Wolowitz file for a patent on their new invention while Penny, Amy and Bernadette give dating advice to Koothrappali after his breakup with Emily.

Original air date
Cast and crew
  • Mark CendrowskiDirector
  • Johnny GaleckiLeonard Hofstadter
  • Jim ParsonsSheldon Cooper
  • Kaley CuocoPenny
  • Simon HelbergHoward Wolowitz
  • Kunal NayyarRaj Koothrappali
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