"The 43 Peculiarity" -- Leonard (Johnny Galecki, left) and Penny (Kaley Cuoco, right) deal with jealousy in their relationship, on THE BIG BANG THEORY, Thursday, Nov. 15 (8:00 – 8:31 PM, ET/PT) on the CBS Television Network. Photo: Robert Voets/Warner Bros. ©2012 Warner Bros. Television. All Rights Reserved.

"The 43 Peculiarity" -- Howard (Simon Helberg, left) and Raj (Kunal Nayyar, center) try to get to the bottom of why Sheldon disappears every afternoon at 2:45, on THE BIG BANG THEORY, Thursday, Nov. 15 (8:00 – 8:31 PM, ET/PT) on the CBS Television Network. Also pictured: Margo Harshman Photo: Robert Voets/Warner Bros. ©2012 Warner Bros. Television. All Rights Reserved.

"The 43 Peculiarity" -- Howard (Simon Helberg, left) and Raj (Kunal Nayyar, center) try to get to the bottom of why Sheldon (Jim Parsons, right) disappears every afternoon at 2:45, on THE BIG BANG THEORY, Thursday, Nov. 15 (8:00 – 8:31 PM, ET/PT) on the CBS Television Network. Photo: Robert Voets/Warner Bros. ©2012 Warner Bros. Television. All Rights Reserved.

"The 43 Peculiarity" -- Howard (Simon Helberg, right) and Raj (Kunal Nayyar, left) try to get to the bottom of why Sheldon disappears every afternoon at 2:45, on THE BIG BANG THEORY, Thursday, Nov. 15 (8:00 – 8:31 PM, ET/PT) on the CBS Television Network. Photo: Robert Voets/Warner Bros. ©2012 Warner Bros. Television. All Rights Reserved.

"The 43 Peculiarity" -- Howard and Raj try to get to the bottom of why Sheldon (Jim Parsons) disappears every afternoon at 2:45, on THE BIG BANG THEORY, Thursday, Nov. 15 (8:00 – 8:31 PM, ET/PT) on the CBS Television Network. Also pictured: Margo Harshman Photo: Robert Voets/Warner Bros. ©2012 Warner Bros. Television. All Rights Reserved.

"The 43 Peculiarity" -- Leonard (Johnny Galecki, right) and Penny (Kaley Cuoco, left) deal with jealousy in their relationship, on THE BIG BANG THEORY, Thursday, Nov. 15 (8:00 – 8:31 PM, ET/PT) on the CBS Television Network. Photo: Robert Voets/Warner Bros. ©2012 Warner Bros. Television. All Rights Reserved.