"The Stockholm Syndrome" - Pictured: Leonard Hofstadter (Johnny Galecki) and Penny (Kaley Cuoco). Bernadette and Wolowitz leave their kids for the first time, Penny and Leonard try to keep a secret, Sheldon and Amy stick together, and Koothrappali makes a new friend as the gang travels together into an uncharted future, on the series finale of THE BIG BANG THEORY, Thursday, May 16 (8:30 - 9:00PM, ET/PT) on the CBS Television Network. Photo: Michael Yarish/CBS ©2019 CBS Broadcasting, Inc. All Rights Reserved

"The Decision Reverberation" -- Pictured: Anu (RatI Gupta) and Rajesh Koothrappali (Kunal Nayyar). Koothrappali is worried people won't take him seriously in his own field after publishing a paper that suggests he may have discovered alien life. Also, Leonard wants to be the principal investigator on a plasma physics study, on THE BIG BANG THEORY, Thursday, April 25 (8:00-8:31 PM, ET/PT) on the CBS Television Network. Photo: Michael Yarish/CBS ©2019 CBS Broadcasting, Inc. All Rights Reserved .

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