Penny tries to seduce an abstaining Leonard to ruin his "donation" for her ex-boyfriend, Zack (Brian Thomas Smith), and his wife, Marissa (Lindsey Kraft). Also, Wolowitz, Bernadette, Anu (Rati Gupta) and Koothrappali turn Koothrappali's canceled bachelor party into a couple's trip aboard the "vomit comet"