The Toast Derivation
Sheldon becomes concerned when everybody begins to hang out at Raj's apartment and discovers Leonard is the center of the group.

Cast
Johnny GaleckiLeonard Hofstadter
Jim ParsonsSheldon Cooper
Kaley CuocoPenny
Simon HelbergHoward Wolowitz
Kunal NayyarRajesh Koothrappali
Melissa RauchBernadette Rostenkowski
Mayim BialikAmy Farrah FowlerThe Big Bang Theory on tvt

