Grace Millane had decided to delay full-blown adulthood for 12 more months. Shortly after she received her degree from England’s University of Lincoln, she tweeted a GIF that expressed her mood as she awaited her flight: Bilbo Baggins sprinting out of the Shire, yelling, “I’m going on an adventure."

A little later, she pecked out “See ya England” and an airplane emoji as she took off for her overseas experience, a year-long trip around the world. She bombarded her family and her followers on social media with pictures of her in the mountains of Peru — the first leg of her journey. A pair of fuzzy llamas posed for her camera.

But the trip’s second leg took a tragic turn.

Days after Millane arrived in Auckland, New Zealand, the country’s prime minister offered apologies to the 22-year-old’s grieving family after the young woman’s sudden disappearance morphed into a murder investigation that has gripped this island nation of nearly 5 million people.

"Your daughter was supposed to be safe here and she wasn’t and I apologize for that,” Prime Minister Jacinda Ardern said, holding back tears.

“From the Kiwis I have spoken to, there is this overwhelming sense of hurt and shame that this has happened in our country, a place that prides itself on our hospitality, on our manakitanga, especially to those who are visiting our shores.”

Police believe Millane was killed sometime between Dec. 1 and Dec. 2, knowledge gained after they spent the past week retracing her steps and those of the chief suspect in her killing.

In closed-circuit television footage from Dec. 1, Millane, in a black dress and her hair down, was seen in the city center of Auckland. Then she was seen at Sky City, an entertainment hub full of bars, restaurants, hotels and a casino.

In one of the final images police recovered of her, she’s seen walking with someone whom police described as a “male companion” at the Citylife hotel on Queen Street, a short distance from Sky City.

By the next day, her family in England knew something was wrong. The onslaught of pictures and videos chronicling Millane’s overseas adventure had suddenly stopped. They expected to hear from her Dec. 2, her birthday, but received only silence.

They contacted authorities. And a few days later, her tearful father was on New Zealand television, pleading for anyone who had seen or heard from his daughter to tell police what they knew. The family, he said, had “grave fears” for her safety.

“As a family, we’ve been extremely concerned for her welfare,” David Millane said. “Grace has never been out of contact for this amount of time. She’s usually in daily contact with either her mother, myself, her two brothers, members of the family on social media. . . . We are all extremely upset, and it is very difficult at this time to fully describe the various emotions that we are going through.”

A little later, police arrested that male companion, although they say a judge has ordered that his name be kept secret to preserve his right to a fair trial.

Investigators have not said anything about how Millane died but have released a timeline of what happened afterward. They believe the suspect rented a red Toyota Corolla hatchback on the morning of Millane’s birthday and drove to an isolated part of the Waitakere Ranges, a coastal park 12 miles from Auckland that is full of native rain forests.

On Sunday, authorities found a woman’s body there. They believe it is Millane’s.

The suspect appeared in court on Monday.

Millane’s father, in New Zealand originally to plead for information about his daughter’s disappearance, attended the initial court hearing for the accused.

“Before we call this matter I’d like to acknowledge the presence of Grace’s family. I don’t know what we say to you at this time. Your grief must be desperate,” Judge Evangelos Thomas said, according to Radio New Zealand. “All of us hope that justice for Grace is fair, swift and ultimately brings you some peace.”

David Millane, father of Grace Millane, speaks at a news conference in Auckland, New Zealand. (Doug Sherring/NZ Herald/AP)

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