Los Angeles is a safe place. Safe, at least, until something insane happens, like the time when one of my neighbours, Robert Lees – a former scriptwriter for Alfred Hitchcock Presents – was beheaded in his own kitchen (with his own vegetable knife) by a passing homeless man. The friend who discovered Lees’s blanket-covered body was asked by the 911 operator to check if he was still breathing – with predictably macabre results. His head was eventually located next door, where his neighbour had come to a similarly gruesome end.

Until recently, stories such as this never bothered me. But over recent months, all that has changed. Up here in the Hollywood Hills, we tremble through the nights, panic buttons at the ready. But it’s not our lives we’re worried about: it’s our silverware, our jewellery, our chequebooks and our cash.

Yes, the cat burglars are out. In recent months a single gang of black-clad thieves has ripped off $8 million of cash and jewellery from houses with security systems so advanced that they could moonlight at Israeli nuclear facilities. Yet so far, these burglar alarms, these miniature green zones, have all but utterly failed. Hence why Sherry Lansing, the former chief of Paramount Studios, is suing the ADT alarm company over the allegation that it took almost two hours for her $25,000 system to call out a dim-witted security guard, who failed to notice any sign of a break-in, leaving the housekeeper to discover the crime scene and dial 911 the next morning.

All of which is immensely reassuring news to me, coming literally days after I spent $2,000 on my own alarm with two touchscreens, multiple door/window circuits and a motion sensor, calibrated to ignore the nocturnal scrabblings of Ginger, my obese cat. I wouldn’t have even bought the damn thing if the old system hadn’t enjoyed waking me up at 4am with a noise so loud it was arguably more traumatic that being robbed. “REMAIN CALM,” the robot voice would bellow from the sky. “THIS IS AN ALERT. REMAIN CALM. THIS IS AN ALERT.” Sometimes the alarm would even scare itself. “INTRUDER! INTRUDER! INTRUDER!” it would begin to chant, bleeping wildly.

And now, like everyone else in LA, I fear my alarm investment may have been wasted. For a start, if you know how to get to the alarm’s battery and power source, you can simply switch it off. And even if the alarm isn’t tampered with, there’s a delay while it calls the company, they call you, you tell them you’re not at home, and they call the LAPD. But if alarm systems are useless, what are worried homeowners to do?

I’ve considered gates, trip-wires, CCTV, machineguns embedded in the lawn sprinklers. But guns scare me. Which leaves only one option: a yard sign from the National Rifle Association. It costs $14.95, comes in bright orange, and declares my front lawn to be “Freedom’s Frontline”. If that won’t scare away a Hollywood cat burglar, nothing will.

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