Image copyright PA Image caption Studio assistants move apart the wax figures of Brad Pitt and Angelina Jolie at Madame Tussauds London following news of their divorce

In a town full of "golden couples," Angelina Jolie and Brad Pitt shone the brightest of them all.

The union of two beautiful actors, both superstars in their own right, seemed to epitomise the movie star dream.

The partnership wasn't just about good looks and winning Oscars - her for Best Supporting Actress in Girl, Interrupted (1999); him as a producer on 12 Years a Slave (2013) - but for global activism too.

Jolie said that filming in Cambodia for Lara Croft: Tomb Raider in 2001 had opened her eyes to the plight of the downtrodden.

"It's the most amazing place I've ever been," she said at the time.

"Being here makes me feel differently about my life, my work, about what we all can do."

It led to the most profound change of all when she adopted a Cambodian orphan, Maddox, who now has five siblings including Zahara and Pax, who were adopted from orphanages in Ethiopia and Vietnam respectively.

In recent years, the entire family were seen occasionally around Los Angeles, doing what families do, going to the park, having breakfast at a restaurant in West Hollywood, almost normal. Almost.

On the red carpet though, Brangelina are something else, almost ethereal, drifting past in a blizzard of flash-bulbs, above the fray.

They always arrive at the last minute, and no photographer leaves until they have swept by.

Image copyright Reuters

For the press, there has certainly been plenty to record and write about in the Brangelina story.

From the start, the tabloids focused on the personal soap opera, speculating wildly on whether Jolie was to blame for the break-up of Pitt's marriage to the actress Jennifer Aniston.

Pitt was still married when he starred alongside Jolie in Mr and Mrs Smith in 2005.

Jolie later said they "fell in love" while filming together, but she denied having an affair.

"To be intimate with a married man, when my own father cheated on my mother, is not something I could forgive," she said.

Her parents Jon Voight and Marcheline Bertrand were actors themselves who split up when Jolie was a baby.

But if it was a movie about a marriage which brought the two together, it was another, a decade later, which may have prophesied the relationship's end.

In last year's By the Sea the pair played a couple whose relationship was on the rocks.

Promoting the film, which flopped at the box office, the screenwriter and director, one Angelina Jolie, told the BBC's Tom Brook:

"It's the reality of marriage that you go through hard times, and that you have to embrace those hard times and challenges and know that that's a part of your marriage, and it's the pulling through together that actually makes the great bond."

"If it was all easy and if it was just two people co-habitating, it's not very interesting, is it?

"Everyone goes through ups and downs. But in the most boring way we're pretty solid."

There didn't seem to be anything boring about their life, their career or their off-screen activism.

As a goodwill ambassador for the United Nations High Commissioner for Refugees and then a special envoy for the UN, Ms Jolie has travelled to refugee camps in more than 30 countries, including Sierra Leone, Darfur, Iraq, Afghanistan and Libya.

"There is a fight to be had… and it's to look after children, to right the wrongs around the world.

"And if there is war, or if there are people suffering, or if there are certain situations that are going unnoticed, then you have to do what you can," she has said.

Pitt, too, is an intensely political celebrity, campaigning for a wide variety of causes, from stem cell research to programmes to tackle poverty and HIV/Aids, to helping victims of natural disasters such as the earthquake in Haiti.

Image copyright EPA Image caption Angelina Jolie bump fists with a Syrian boy during her visit to Azraq Syrian refugee camp

An interest in architecture was even harnessed to a cause when he started a foundation to help with environmentally friendly rebuilding in New Orleans following Hurricane Katrina.

"It's a justice issue," he told MSNBC. "What we saw in Katrina is that there is unfortunately a portion of society that has been overlooked.

"Maybe we can find some good out of this and that has to do with justice and fairness."

Back in Hollywood, the rumours swirl, as rumours do, with claims about an affair, substance abuse and fights over the children.

Of course only two people really know what went wrong.

But in a town where gossip flows like the martinis at Musso and Frank's, a handful of well-informed celebrity journalists reckon they have a pretty good idea.

The website TMZ, which broke the story (it breaks all such stories these days), dismissed talk of infidelity, insisting that the issue was over parenting disagreements

Whatever the reason, the divorce will bring to an end not just a marriage but a name.

Brangelina is no more.