2006 Chevy Malibu I get nothing. Please help

Car has been running perfectly. Went out to start it this evening and nothing. No power anywhere. No electric door locks, no lights at all, no crank, the only thing I noticed was a slight ticking sound and the "lock"warning light on the dash would flicker every 6 seconds while the key was in the ignition. Could this be some sort of an anti-theft device gone wrong?