Protesters hold up missing person notices for five people affiliated with the Mighty Current publishing house in early January. (Anthony Wallace/Agence France-Presse via Getty Images)

Angela Gui, 22, a university student in England, and her father, a publisher who lives on the other side of the world, don’t get to see each other as often as they would like. But they spent a happy Christmas together in 2014, and last fall Angela was looking forward to seeing her father again in November.

A month before they were to meet, he went missing.

Angela knows that her father, Gui Minhai, did some shopping on the morning of Oct. 17. A video camera in his Thai condo showed him returning home with his groceries, carrying them upstairs and then driving away again with a man who had been lurking in his garage.

Angela has not spoken with her father since, although she has received messages from him — or someone who claims to be him.

This is a mystery, then, and a missing-person story, but not of a conventional kind. Gui is missing from public view, but we can be fairly certain that he is in a prison somewhere inside China.

He was born in China, in 1964, and traveled to study at Sweden’s University of Gothenburg in 1988. The following year, China’s Communist Party crushed peaceful pro-democracy demonstrations in Tiananmen Square. Gui spent the next decade in Sweden, becoming a citizen, earning his PhD and having a daughter, Angela, his only child, who also is a Swedish citizen.

As the political climate in China relaxed, Gui returned, and eventually helped establish a company in Hong Kong that published gossipy volumes about China’s leaders. Last fall it had a potential blockbuster in the works: a biography of Chinese President Xi Jinping.

The book has never been published.

All Angela knew, at first, was that her father uncharacteristically had stopped communicating.

Eventually her father’s friend and colleague in Hong Kong, Lee Bo, sent her an email: “ ‘Your dad has gone missing. We’re afraid he was taken by Chinese agents for political reasons.’ . . . That was an incredible shock,” she said.

Gui’s car has never been found. Thailand claims to have no record of his leaving the country. But in November, Angela received a brief text message purportedly from him. “I hope you will be fine,” it said.

Angela, whose soft-spoken British-accented English carries barely a trace of her native Swedish, paused to compose herself as she recalled that time.

“He didn’t respond to my messages,” she said. “It was clear to me by then that somebody was controlling him.”

In December came another shock: Lee also disappeared, apparently abducted from Hong Kong as Gui was from Thailand.

“I knew he had British citizenship,” Angela said. “He had said, ‘As long as I’m still in Hong Kong, I’ll be okay.’ ”

It was not unheard of in years past for China’s Communist rulers to reach beyond their borders to silence critics. In 2002, they kidnapped democracy activist Wang Bingzhang from Vietnam; he remains in a Chinese prison to this day.

But the brazenness and frequency of such actions have been growing. Overseas Chinese who speak out discover that relatives inside China have been jailed or threatened. And altogether, five employees of Gui’s Hong Kong publishing house have been disappeared for periods of time.

Lee eventually resurfaced in Hong Kong. He delivered a bizarre statement regretting his involvement with the publishing house, praising China and refusing to provide any information about his disappearance. He then went missing again.

Gui’s reemergence was even odder. In January, he appeared on Chinese television, tearfully claiming to have voluntarily returned to China to take responsibility for a hit-and-run accident in 2003.

Angela has yet to watch the supposed confession from beginning to end. “I’m trying to stay focused on getting him released,” she said. “If I watched the whole thing, with my father in tears, I don’t think I could go on.”

But she has watched enough to know it is false. “That’s just not the way he talks,” she said. She had never heard him speak of any accident.

Compounding her misgivings is one final message she received from his Skype account.

“He said he was okay, that he went back to China on his own to solve his own problems. ‘If anyone asks about me, please keep quiet, because that’s important to me.’ ”

“I replied, ‘What do you mean? Where are you?’ ” But there was no response.

Angela, a sociology major who never expected to be an activist, finds herself knocking on official doors in Stockholm and Washington, hoping that governments eager for smooth relations with China will stir themselves to object to such egregious behavior.

“Even though he told me to keep quiet, I don’t believe that’s his actual wish, and I believe that if I did keep quiet, I would just be assisting in a crime against international law,” she said.

“I hope that’s the right thing. I don’t know.”

She paused again to compose herself.

“It’s been seven months now, and I’ve not heard a thing.”

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