Mike Segar/Reuters

When the billionaire George Soros makes headlines, it’s usually in the business section. A lawsuit that has been filed in New York has now pushed his affairs into the gossip pages.

Adriana Ferreyr, a 28-year-old companion of Mr. Soros for many years, is suing the 80-year-old businessman in New York Supreme Court in Manhattan, alleging he reneged on two separate promises to buy her an apartment, causing her extreme emotional distress. A former soap opera star in Brazil, Ms. Ferreyr says that Mr. Soros’s assurances of an apartment were more than just pillow talk, and that she invested months looking for a place to call home and hired brokers and designers to help in her hunt.

“Soros not only breached his multiple promises, which were reasonably relied upon by Ferreyr to her detriment, but he also proceeded to engage in a deliberate and malicious campaign of extreme and outrageous harassment and intimidation against Ferreyr, which has directly resulted in her suffering and continuing to suffer severe emotional distress and damages,” her suit says.

Ms. Ferreyr is suing Mr. Soros, who is celebrating a birthday Friday, for $50 million. Many of her causes of action center on emotional distress, said Robert J. Hantman, Ms. Ferreyr’s lawyer.

William Zabel, a lawyer for Mr. Soros, said the suit was “frivolous and entirely without merit.” He said Mr. Soros had an “on-again, off-again and nonexclusive relationship,” but Ms. Ferreyr’s complaint was “riddled with false charges and is obviously an attempt to extract money from my client, who is a very wealthy man.”

He said his client was considering a countersuit, but declined to comment further.

Related Links The complaint

The story begins in 2006, when Mr. Soros met Ms. Ferreyr in the Hamptons. He invited Ms. Ferreyr, who owns her own retail business, selling sunglasses and Christmas ornaments through kiosks in malls on the West Coast, to meet for tea and got her phone number. Things developed, and by 2007 she and Mr. Soros were in a “serious and meaningful” relationship and considered a couple both here and abroad, the complaint says.

In 2009 Ms. Ferreyr started shopping around for an apartment. She was looking in the $1 million range but fell in love with an apartment on the Upper East Side worth $1,995,000. During a trip to the Caribbean she mentioned to Mr. Soros she had found her “dream home” but was worried she couldn’t afford it. Mr. Soros later told her not to worry about the cost, that he wanted to “make her happy” and that he would buy the apartment in his company’s name.

“Soros specifically stated, “Don’t worry it is yours, I am only putting it in the name of a company for tax purposes as I want to avoid paying gift taxes,” the complaint says.

In early 2010 Ms. Ferreyr made an offer on the apartment and hired a designer, and Mr. Soros’s company signed a contract to buy the apartment.

That was where things went south. In March, immediately after the apartment closed, Mr. Soros broke up with Ms. Ferreyr. Ms. Ferreyr was distraught, but was hopeful the split was only temporary. She continued to live in another apartment while finishing a semester at Columbia University.

In June the couple got back together and later that summer, while lying in bed, Mr. Soros dropped a bombshell on Ms. Ferreyr about the apartment. “I gave it to my girlfriend and she is flourishing,” he said, according to the complaint.

She contends that a fight ensued. He slapped her, tried to choke her and then threw a lamp at her, according to the complaint. She ran to another room and called the police.

Mr. Zabel, Mr. Soros’s lawyer, disputes this claim. “The police investigated the August 2010 incident referred to and concluded that no assault occurred,” he said. “George Soros did not slap, choke or throw a lamp at her. We will seek dismissal of this baseless lawsuit as soon as possible.”

A police report of the dispute indicates she told officers that “a nearby lamp fell on her right foot.” Ms. Ferreyr, the police report indicates, was not “fearful” at the time of the police visit.

She went to the hospital for the stitches, and after the event became “extremely traumatized and emotionally distressed,” the complaint says. She withdrew from one of her classes at Columbia, where her lawyer says she is studying philosophy.

In November the pair saw each other again. The complaint says Mr. Soros said he felt bad about what had happened and told her to start looking for an apartment right away. The romance was back on.

Ms. Ferreyr hired a new real estate broker and found another apartment, valued at $4.3 million, in the same building as the first apartment. And again, the complaint says, Mr. Soros got cold feet and reneged on his promise to buy an apartment, causing more emotional distress to Ms. Ferreyr.

In April of this year, Mr. Soros offered Ms. Ferreyr an undisclosed sum of money if she agreed to sign a release saying she would not sue him or discuss their relationship for five years. She refused to sign the agreement. Instead she tried to lease yet another apartment in the same building.

This, according to the complaint, caused Mr. Soros distress because his other girlfriend was now living in the building. “Soros did not like the fact that both women were living in the same building and therefore wanted Ferreyr to move out,” the complaint says.

Ms. Ferreyr says at this point Mr. Soros began harassing her and hired private security officers to follow her, causing her even more anxiety. Ms. Ferreyr eventually moved into the building, into a friend’s apartment, and is currently residing there.

Ms. Ferreyr, the complaint says, “continues to fear for her safety, which only serves to add to and heighten the emotional distress and anxiety from which she is suffering, as a direct result of being constantly watched and stalked by Soros’s private security detail.”

The New York Post earlier reported on the lawsuit.

Ferreyr v. Soros