I hope the Johnny Swing (what skilled Lindy-Hoppers call the frantic and dangerous pseudo-swing now being performed by club kids) will be kept to a minimum when San Francisco’s the New Morty Show plays the Chevy Chase Ballroom tonight, but I’m not making any bets. Unlike more traditional swing bands, like D.C.’s stellar Tom Cunningham Orchestra, the Morty Show is steeped in the postmodern camp and irony of lounge, which always has been more about hip than hop. Led by 28-year-old Morty Okin and singer Connie Champagne, the 10-piece outfit bills itself as the second coming of ’50s Vegas gods Louis Prima and Keely Smith. Still, the band sounds terrific on its new disc Mortyfied, even if it does cover Billy Idol and Metallica. It’s probably worth a few sore toes. At 9 p.m. at the Chevy Chase Ballroom, 5707 Wisconsin Ave. NW. $15. (202) 363-8344. (Mark Gauvreau Judge)