236 The Big Bang Theory The Proton Transmogrification 07 22 2014-05-01 Comedy / Romance Jim Parsons - Sheldon Cooper / Johnny Galecki - Leonard Hofstadter / Kaley Cuoco - Penny / Kunal Nayyar - Rajesh Koothrappali / Simon Helberg - Howard Wolowitz / Melissa Rauch - Bernadette Rostenkowski / Mayim Bialik - Amy Farrah Fowler / Laura Spencer - Emily Sweeney / Sara Gilbert - Leslie Winkle / Kevin Sussman - Stuart Bloom / John Ross Bowie - Barry Kripke / Carol Ann Susi - Debbie Wolowitz Professor Proton helps Sheldon deal with grief; Leonard gets into a competition with Penny; Bernadette and Amy prepare a "Star Wars Day" gift for the guys.