With a spa, a swimming pool, two heliports and room for 18 guests, the Luna is more like a floating luxury villa than a yacht. The lifeboats cost $4 million apiece. Gleaming engines propel the vessel at a maximum speed of 22 knots.

But for now, the Luna isn’t moving. It sits in Dubai, the most fought-over prize in what has been called Britain’s most expensive divorce.

In December 2016, a High Court judge ordered Farkhad Akhmedov, a Russian billionaire who has owned a home in England since the 1990s, to pay the equivalent of $646 million to his ex-wife, Tatiana Akhmedova. He refused, arguing that the couple had been divorced in Russia more than a decade ago.

Unconvinced and unable to enforce his ruling, the judge in April ordered Akhmedov to give the yacht, valued at roughly $500 million, to his ex-wife. It has since been impounded by authorities in Dubai.

For more than a decade, Russian oligarchs have been parking their families and some chunk of their net worth in England. Now some oligarchs are learning that life here has hazards of its own — even for nonresidents like Akhmedov.

As the nine-figure settlement was gaveled into divorce court history, Akhmedov began what the judge called a “campaign” to hide his assets. Nothing demonstrates the breadth of that web like the Luna. Starting in November 2016, the yacht went on a whirlwind voyage, all on paper, in a feat of asset protection and financial engineering.

Initially, the seizure of the yacht sounded like a setback for Akhmedov. Then, he and lawyers for the family trust that technically owns the Luna filed a claim — still pending — arguing that the fate of the yacht should be decided by a court in Dubai. Legal experts say Akhmedov has calculated that his odds of prevailing are better in a sharia court. Stories in British tabloids have lately emphasized that Akhmedov is a practicing Muslim.

That is news to his ex-wife. She said she had never seen her ex-husband kneeling on a prayer rug or going to a mosque, other than at a tourist site. “Apparently because he was born in Azerbaijan, he’s a Muslim,” she said.

Akhmedova said she was reluctant to speak publicly about her divorce, because everything about it is painful, including allegations of infidelity leveled by both sides.

She’s also startled by Akhmedov’s campaign to keep her from pocketing 1 cent of his $1.4 billion fortune. She said she had always wanted to settle out of court, quietly and for far less than she was awarded.

She still speaks fondly of the years she spent with her ex-husband, whom she says she met in Moscow in 1989, when she was 17. He was nearly twice her age. “He struck me as a very proper gentleman,” she said.

The two married in 1993. He started off in the fur business, selling sable skins on the London Commodity Exchange. He pivoted to the natural gas sector and, in 2012, sold his 49 percent stake in Northgas for a reported $1.4 billion.

Over the years, he acquired a summer house in the south of France, two helicopters, vintage cars, fine art and a $26 million home outside London. “We went from flying Aeroflot to British Airways to chartered flights,” said Akhmedova. Later, they flew on their own $50 million private jet.