Geeky Brian has built a device that he hopes will make his bitchy stepsister Olivia act nice towards him but when he tries it on her it turns her into a horny zombie. Rodney's scientist friend turns his girlfriend into a horny zombie.
When Brian discovers his stepsister Charlotte doing a sexy webcam show he blackmails her into performing sexual favors. Brian's stepmom gets a job at a massage parlor where her stepson Rodney is her first customer.