"After looking at the watch, the suspect began asking about repairing his Vertu phone," police said in a statement.
Police say the clerk put the watch down on a chair and briefly left the counter as the man made a phone call. They say that's when the man slipped the watch into his back pocket and walked out of the store.
The man was seen on store security video. He's described as being of Middle Eastern descent, in his 50s, about 6 feet tall and weighing 185 pounds. He wore prescription eyeglasses.
Anyone with information about the case should call detectives at (818) 548-2097, or dial (800) 222-TIPS (8477).
City News Service contributed to this report.