Youths get ready for a party, decorating the dance floor, cleaning out the fountain of a pond. That evening, the party starts and guests arrive: everyone has a ticket, and a guy at the gate, wearing a formal shirt, tails, and shorts, makes sure only those with tickets gain entrance. Some are in costume, some dressed informally, some in fancy clothes: everyone is there to have a good time. A group of tough-looking guys watch through the high fence while the band plays jazzy rock and couples dance or kiss. With the party in full swing, as the band plays “When the Saints Go Marching In,” over the wall comes the gang. Is there any chance they’ll join in the festivities?