Antoinette de Lisser, 37, has a nickname at work: Legend. She is so well known by it that it even forms part of her e-mail address — and, indeed, much of what she has accomplished has been the stuff of company legend.

For instance, there was the time when her boss, Trevor Beattie, dispatched her to Miami to get a British girl out of jail. “Trevor heard the story on the radio: she was 21, had had a few drinks and made the stupid mistake of saying at the airport that she had a bomb in her pocket. The authorities overreacted. I escorted her frail father over to Miami and spent a few days working with the police and lawyers to bring her back.”

When Trevor arrived at work with a book that he wanted Bill Clinton to sign, Antoinette was unfazed: “I didn’t see what the title was at first, but Trevor said that Clinton was signing his autobiography at Waterstone’s in Piccadilly. It was only when I got there and joined this long queue that I saw the book was Monica Lewinsky’s signed autobiography.

“Anyway, I queued for six hours and I was 20 people away from the doors when they closed them. I hate failure, but I called a taxi and was just about to go when I realised that Clinton was about to leave.

“I stood on the kerb and called out ‘Mr President!’ as he came out, and managed to put the book in front of him. He didn’t have a clue what he was signing.”

Once, Antoinette was working alone late one evening and the phone rang: “This lady asked to speak to Trevor and said she was the Duchess of York. I said ‘Oh yeah, right, and I’m Charlie in the chocolate factory — how long do you want to keep this up for?’ It turned out that the caller really was the Duchess. She burst out laughing and said it was a long time since anyone had spoken to her like that. The next day she called back and passed the phone round to her daughters.”

Antoinette has worked for Trevor for four years, first at the advertising agency TBWA London. Two years ago he set up Beattie McGuinness Bungay. “I’d been 14 years in my previous job,” he says. “I was chairman and earning a pile of money. I wanted to be scared again and stand at a wicket with nought against my name.”

Antoinette took little persuading to join him in the new enterprise, which now employs 63 people and won 12 of its 15 pitches for business last year. “Today we won the Pretty Polly account, so we’ll be celebrating,” says Trevor.

The company would not have achieved its successes without Antoinette: “She really is a living legend. She is extremely resourceful and no challenge is beyond her. I lead a funny life, with interests in art and charity. We never know what will happen next and she never knows where I’ll call from.

“Once I got halfway to Australia and was at Singapore when I realised that I didn’t have a visa. She arranged it digitally there and then.

“It’s a difficult job that she does, but she does it with skill and is the life and soul of the place. She has charm, charisma, intelligence, diplomacy, patience, strength of character, stamina, organisational skills and, when required, sheer bloody-mindedness.”

Antoinette, who also looks after Trevor’s personal life, was a runner-up in The Times Crème Hays Secretarial PA of the Year competition. She agrees that her role is challenging: “It is made more difficult by the fact that Trevor’s interests are so varied, but my mantra is that nothing is impossible.”

She juggles travel arrangements, extensive diary management and meetings, arranges functions, deals with journalists and does a great deal of research as well. The job means being able to book tables in the most exclusive restaurants at a moment’s notice, and to cajole items from the rich and famous for charity auctions.

Antoinette has also worked in sales but nowadays considers herself a career PA: “The best advice I was given by one former boss was to get out of working in banks and institutions, as she thought that my personality was too big,” she says.

“The past four years with Trevor have simply been the best. We’re having the time of our lives.”

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