You can show anything on network television these days—except lighted cigarettes. The producers of ABC’s new show Pan Am, about stewardesses in the 1960s, have announced that the network will not allow them to show the characters smoking. Producer Thomas Schlamme told Entertainment Weekly that this is “the one revisionist cheat” in a show that will otherwise try to get period detail right. Though TV characters on shows like Two and a Half Men are sometimes shown smoking cigars, cigarettes have become taboo on broadcast television due to what Schlamme calls the “impressionable element,” the fear of influencing viewers. (It doesn’t help that, unlike liquor, cigarettes can’t be advertised on TV, so the networks can’t make money plugging the products.) But shows on cable have no such fear of bad influence: the characters on Mad Men light up all the time. Of course, it helps that hardly anyone is watching.