She took a Lyft ride an hour later to the northern part of the city miles from where she lived, and vanished, police said.
A week later, Lueck’s friends fear for her safety as police scour for clues throughout the city.
“She threw a birthday party for her cat, so for her not to come home to her cat is not adding up,” friend Ashley Fine said during a news conference on Sunday.
Police said they have interviewed the Lyft driver and that the ride-hailing company was cooperative, and they have not discovered any information that would lead them to think Lueck was harmed or in danger.
Lueck was dropped off at Hatch Park to meet an unidentified person waiting in a vehicle around 3 a.m., Assistant Chief Tim Doubt said at a Monday news conference. The park is about an eight mile drive in another direction from her home in Trolley Square on the eastern edge of downtown.
The Lyft driver said Lueck did not appear distressed when she approached the other vehicle, Doubt said.
There is no evidence of foul play, Doubt reiterated Monday. That had restricted police from using investigative tools such as combing through Lueck’s bank records and cellphone activity, said Sgt. Brandon Shearer, another police spokesman.
“Adults have the ability to not be found if they don’t want to,” Shearer said. However, Lueck was scheduled to return to California on Sunday but missed her flight, and that gives police “more cause of concern,” Shearer said.
On Tuesday, police released photos of Lueck at the airport they said were the last known images of her before the disappearance. Doubt had a message for Lueck at a news conference.
“Mackenzie,” he said, “in the case you just want to be left alone, please let us know you are safe.”
Lyft said Lueck’s route “contained no irregularities” and ended at the scheduled destination, said Lauren Alexander, a company spokeswoman. The driver continued on to pick up other riders, she said.
That has only compounded the mystery for Lueck’s friends. Fine said she was unaware of Lueck having a significant other or any reason she would venture 20 minutes in the opposite direction from her home.
Kennedy Stoner, a sorority sister, said it was “very unlike” Lueck not to check in with her.
“We don’t believe she would miss a midterm because she was stressed. I am positive something is wrong,” Stoner said. “I don’t believe she would go off and not contact one person.”
Lueck’s friends have handed out missing-person fliers and pleaded on Facebook for more information to assist the police.
“Kenzie, if you can hear this, we are all worried and we are looking out for you 24/7,” Stoner said. “We are not able to sleep. I cannot sleep at night knowing you are out there. Please let us know if you are safe.”