MEXICO CITY (AP).- Dozens of plastic foam heads rain onto the stage. Four drug traffickers in fringed jackets and sparkly pink cowboy hats bat them into the audience with toy AK-47s. All the while, the cast croons, “Let them slit our throats, let them pack us up … let them not ask any questions, let them not investigate.” Like other aspects of Mexican society, violence now pervades the arts. From paintings to movies to opera, the killings and kidnappings that dominate headlines are now the topic du jour for artists trying to process what’s happening to their country. Many artists say they also hope their work helps to spark change in a society that seems to be growing numb to the daily bloodshed.