"Bad Eggs" is the twelfth episode of the second season of Buffy the Vampire Slayer, and is the twenty-fourth episode in the series. It was written by Joss Whedon and Marti Noxon and directed by David Greenwalt. It was originally broadcast on January 12, 1998. Buffy and Scooby Gang encounter even more trouble than they expect when the eggs they are given in health class turn out to be prehistoric parasites that take over their lives.