It will be the millionaire gunshoe's second marriage and, he says, his last.

As a token of his affection for Justine Sadokierski, 22, Frank has presented her with an emerald ring studded with diamonds and valued at $100,000.

"The 7.5 carat emerald was given to me by the Sheik of Dubai almost 20 years ago as payment for work I'd done for him. I never thought I would ever part with it," says Frank (pictured with Justine). "It's a beautiful stone - pale and sparkling, and it's only matched by Justine's beauty."

And of Frank, Justine says: "He's a generous, successful, powerful, charming man and I love him very much. We're on the same wavelength despite the age difference. We both enjoy the same things - dining out, going to a show, and we even go to the gym and work out together.

"Age is only numbers. Really, it doesn't even come into my considerations."

The couple met about two years ago at a coffee lounge in Sydney's Double Bay.

Justine has since become office manager at Frank's detective agency and has also been on assignment. She has become adept at 'tailing' people and gaining vital information for clients.

"Not only does Justine run the office like clockwork, but she is a fantastic detective," Frank says.

He recalls first seeing Justine sitting alone in a cafe, so he walked into the half-empty premises and asked politely if he could sit at her table.

"I was taken by her beauty and poise, but when she told me to go away, I was mortally wounded," Frank says.

According to Justine, Frank kept appearing everywhere she went. Little did she know that he was using his surveillance skills to meet her.

"Eventually," Justine says, "we met through a mutual friend and fell in love."

Since then, the one-time fashion designer has 'infiltrated' social functions, tracked subjects interstate and, on one occasion, spied on Madonna during business negotiations in the U.S.

However, Justine has no intention of remaining an inquiry agent.

She says: "That's Frank's expertise. I intend to go back to fashion designing and perhaps start my own label. I have a number of business projects in mind that I can't talk about yet."

As a private eye during the past 20 years, Frank has travelled the world working for high profile personalities, including Arab sheiks, the Rockefeller family the late Aristotle Onassis.

"I know Frank's been there and done that, but I also know he has settled down a lot," Justine says. "I can only repeat that we are both very much in love and his two sons have accepted me and our relationship.

"They are my age, but there is no jealousy or mistrust. They accept that I love their father."

As for Frank, he says he is more than ready to marry his "angel" in September.

"Justine is something special and has added a new dimension to my life."

Story: Norm Lipson Picture: Bill Anagrius