It has been nearly a week since Hatice Cengiz, 36, last saw the man she planned to marry, Jamal Khashoggi, a prominent Saudi journalist and critic of the Saudi government. She is the only witness to his disappearance.

Khashoggi entered the Saudi Consulate in Istanbul at about 1 p.m. last Tuesday to finalize papers for their wedding. Cengiz had said she’d wait for him near the front entrance. “Fine, my darling,” he said, before turning and heading into the squat yellow structure.

Khashoggi, 59, has not been heard from since.

Turkish officials have said they believe he was killed inside in a planned murder. A team of 15 Saudis arrived on two planes to carry out the killing, officials have said.

Cengiz has not been told whether Khashoggi is alive or dead.

Saudi officials insist that Khashoggi left the consulate alive, through a back entrance. Officials at the consulate declined interview requests.

Saudi Arabia’s ruthless response to dissent

If Khashoggi’s death is confirmed, it would represent a new level of audacity in Saudi Arabia’s clampdown on dissent under Crown Prince Mohammed bin Salman. While painting himself as a reformer, Mohammed has shown himself to be ruthless in confronting any challenge to his power, jailing activists and dissenters.

Once close to the Saudi establishment, Khashoggi had in the past year become one of its most high-profile critics, living in Virginia in self-imposed exile and contributing to The Washington Post’s Global Opinions section.

Key to the Turkish investigation could be surveillance footage from the streets adjacent to the consulate. At least six closed-circuit cameras are positioned at the front entrance of the consulate next to its barbed-wire-topped walls. Some of them are maintained by Turkish police.

When Cengiz was first interviewed by police, on the day Khashoggi disappeared, she was presented with a still from one of the cameras that showed him walking in.

“Is this him?” they asked her. She confirmed that it was — in the dark jacket that he had been wearing.

At least four cameras keep watch on the garage and the back entrance. Three more are pointed at the road next to the back entrance, mounted at a primary school across the way. The footage has been retrieved by Turkish intelligence, according to ISS, the firm that handles security at the site.

Cengiz said she skipped her classes at the university where she is studying for a doctorate to accompany Khashoggi to the consulate. They spent the taxi ride there discussing their future.

How they fell in love

Cengiz’s father had consented to the marriage last month when Khashoggi went to ask for her hand. Turan Kislakci, a friend of Khashoggi’s who went along to translate, said her father had initially been skeptical because of the age gap.

Khashoggi had bought an apartment for himself and Cengiz in Istanbul, which they had just furnished.

In an interview with The Post, she recounted their love story, as she had for the police earlier in the day. The pair met at a conference in May. Cengiz has an interest in the Persian Gulf states, and she said she had admired Khashoggi’s work before they met. He was a speaker at the conference, and she had asked him a question. Afterward, she asked if they could talk in more depth. They sat in a corner and chatted.

They stayed in touch, then met when he visited Istanbul. “The connection got stronger and stronger,” she said.

Since Khashoggi’s disappearance, some pro-Saudi accounts online have questioned whether Cengiz is part of a plot to discredit the kingdom.

As a response, she scrolls through selfies of the two of them in the summer, smiling and pressed close. “I really exist, and he is my fiance,” she said.

Khashoggi was relatively at ease as they approached the Saudi Consulate, she recalled. He had been concerned before their first visit a week earlier.

“He said at some point, ‘Maybe it’s better if I don’t go,’ ” she said. “He was worried that something might happen.”

But he had changed his mind.

Kislakci, who is head of the Turkish-Arab Media Association, said he had sought assurances about Khashoggi’s safety from people he knew who were close to Mohammed, as did another friend in London, who declined to be named.

Khashoggi was determined to get married, Cengiz and friends said. To wed a Turkish national in Turkey, he needed a document that proved that he was divorced. He had been treated well when he had first visited the consulate and was told to return in a week.

‘Where is Jamal?’

It was around 4 p.m. when Cengiz started to realize that something was really wrong. She checked the consulate’s closing time on the Internet — 3:30 p.m.

“That’s when I began to ask, ‘Where did Jamal go?’ ” she said. She called a friend as she walked to the gate. “My friend told me that I didn’t sound normal when I called her,” she said. “I was out of my mind.”

She asked a guard: “Where is Jamal?”

She called the consulate: “Where is Jamal? I am waiting at the entrance. Jamal entered and didn’t come out.”

A man came to the entrance. “There’s no one inside,” he said.

Khashoggi had previously told her to call an adviser to Turkish President Recep Tayyip Erdogan if anything happened to him. She did. And she reported the disappearance to police.

But solid information has been slow in coming from Turkish authorities. She is frustrated with the lack of information she has received.

“As his fiancee, as someone close to Jamal and in love with Jamal, I am waiting for information from my government about what has happened to him,” she said. “Where is Jamal?”

Ultimately though, she said, it is up to the Saudis to back up their story.

“It is the responsibility of Saudi Arabia to explain and prove how Jamal exited and from where and when,” she said.

Until she has proof otherwise, Cengiz continues to believe he may be alive.

She scrolls back to her last text message from him. “The house is beautiful, like its owner,” he wrote of their apartment.

“I am not giving up hope,” she said. “I hope we will soon learn what happened to him, and I still have hope that he is alive. But I need to know, where is Jamal? I have to know what has happened to him.”

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