It will be a big night on CBS this Thursday. "The Big Bang Theory" is coming to a close with two back-to-back episodes, followed by the second season finale of "Young Sheldon."

A special, "Unraveling the Mystery: A Big Bang Farewell," will then air at 9:30 p.m. ET. It stars Johnny Galecki and Kaley Cuoco, taking viewers behind the scenes of the comedy series that debuted in 2007 and is the longest-running multi-camera comedy series in TV history. 

"The Big Bang Theory" has received 52 Emmy Award nominations and 10 wins, and seven Golden Globe nominations. "Young Sheldon" is a spin-off prequel to the show, giving audiences a chance to know Sheldon Cooper as a child. 

Schedule: 

  • The Big Bang Theory series finale -- 8:00 p.m. 
  • Young Sheldon season finale -- 9:00 p.m. 
  • Unraveling the Mystery: A Big Bang Farewell -- 9:30 p.m. 

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