A college girl is raped at a fraternity party, and it is discovered that the date rape drug GHB was put into her drink. The SVU detectives learn that her drugging was not done by the fraternity guy with whom she had sex but was, instead, an act of revenge by one of her jealous sorority sisters. Can Cabot get convictions against the sorority girls as well as the fraternity guy who believed the sex was consensual?