America's city of Angels haunted by visions of the apocalypse

Under the shadow of Los Angeles' very own twin towers, the triangular skyscrapers that rise arrestingly out of the almost uniformly flat city skyline, there has been one dominant thought since the morning of 11 September: my God, we could be next.

Under the shadow of Los Angeles' very own twin towers, the triangular skyscrapers that rise arrestingly out of the almost uniformly flat city skyline, there has been one dominant thought since the morning of 11 September: my God, we could be next.

It was the first thought that struck city officials after they saw the television images of planes crashing into the World Trade Centre in New York. Learning, in those first frenzied moments, that at least two of the hijacked planes were en route to LA, the first thing they did was to evacuate the towers and most of the high-rise office buildings around them.

And that sense of alarm has scarcely abated since.

"We didn't know, that first morning, whether we were supposed to come to work or not," said Jim Selman, a PR consultant whose fifth-floor office window is filled by the same 1970s-era steel and glass vista that once was so familiar in lower Manhattan. "Some days, I'm still not sure. My workload has been up and down like a seesaw."

The area around the twin towers, known as Century City because it was once the back lot of the Twentieth Century Fox studios, has come to symbolise all the anxieties and fears of the post-11 September world for millions of people living in the immediate vicinity, from Beverly Hills to Venice Beach.

For a couple of weeks, the open-air shopping mall adjacent to the towers was all but deserted. One entertainment company in negotiations to lease office space in the towers decided to look elsewhere. "Don't go to Century City," was the advice whispered around west LA's comfortable suburban neighbourhoods.

The crowds have now trickled back. At least a part of LA's inveterate shopping class – toes all manicured and sunglasses neatly propped just above the hairline – is out again, chatting in the shopping centre cafés about clothing styles and boyfriends as if nothing ever happened. But the signs of unease are clearly on display, from the "Let Freedom Ring" placards in empty mall corridors to the 40 per cent discount tags in the leather coat shops.

And everywhere is security, security, security. Before the attacks, you could wander into one of the twin towers and take an elevator to any floor you cared to without being challenged. Now the underground car park beneath the towers has been closed off to casual visitors and shoppers, photographs are forbidden and at every turn there are armed guards.

All sense of fun has vanished, and that includes the local cinema, unable to entice moviegoers who don't happen to work in Century City, and the Shubert Theatre, which closed for good on 13 October after a final run of the Cole Porter musical Kiss Me Kate.

One lunchtime earlier this week, office workers well used to dealing with the media – many of them work in entertainment or PR or high-profile law firms – averted their eyes and seemed reluctant to talk when approached by a journalist. Even those who agreed to say a few words did not want to be named for fear of trouble from their employers. One made nervous eye contact with a security guard who ran over and declared: "I'm sorry, but I'm going to have to ask you to leave."

Now, the anthrax scare has made everyone jittery all over again. Companies have sealed their mail rooms and put their staff through emergency evacuation procedures. In watercooler chitchat, workers are speculating whether it is better to iron suspicious mail or zap it in the microwave (apparently, ironing is more effective). And nobody is going to the Century City post office any more – even at lunchtime it was virtually deserted.

As the winter season approaches, the sense of foreboding is only growing. "I don't even want to be here on Hallowe'en," a customer service representative at the shopping mall confided, despite her official role in reassuring shoppers that they are quite safe.

To believe some of the swirling rumours, Hallowe'en is when the terrorists will strike again. Clearly, many people do believe it. The representative went on: "If they get to the shopping malls, God forbid, and start targeting large numbers of innocent people ..." She was too overwhelmed with anxiety to finish the thought.