“The Big Bang Theory” cast planned a surprise birthday cake for Kaley Cuoco, who plays Penny. Jim Parsons, who plays Sheldon on the show, was so excited for Cuoco that he posted a picture of the cake. On Instagram he posted the cake saying: "almost time, @kaleycuoco ... shhhhh...." Parsons later posted another photo of Cuoco holding her phone with the picture of the cake on it. According to Comicbook.com, this is the final season of “The Big Bang Theory.”