The Donation Oscillation
Penny tries to seduce an abstaining Leonard to ruin his "donation" for her ex-boyfriend, Zack, and his wife, Marissa. Also, Wolowitz, Bernadette, Anu and Koothrappali turn Koothrappali's canceled bachelor party into a couple's trip.

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

