The sitcom premise of a woman finding a new roommate whose character attributes are the exact opposite of hers will be used by 20 new shows this fall, including four on the same night as part of CBS’ Tuesday night lineup.

“Well, you know, the characters don’t have the same name in each show so we thought it was different enough to have them all on the same night,” said CBS president Leslie Moonves.

“It’s the same model we’ve been using for the past 10 years to make our network the highest rated on television.”

ABC, which is using the premise in three new shows this fall, hopes to attract the sorority girl audience.

“We really need to increase our advertising revenue, and sorority girls will basically buy anything as long as an attractive blonde girl tells them to; so we think these new shows will really help us,” ABC president Anne Sweeney said.

NBC and FOX have new shows with the same sitcom premise as well, but many industry insiders believe that instead of catering to the advertisers these channels will instead try to make them intellectually stimulating, a move that will undoubtedly keep them from lasting more than one season.