Shia LaBeouf, the mercurial actor known equally well for box office hits and bizarre performance art, took up a 24-hour residence on Friday in a tiny, makeshift performance space at one of the most prestigious universities in the world, where he said he would chat with any visitor willing to brave the long lines and the cramped quarters.
The university? Oxford. The space? An elevator.
The student union had invited Mr. LaBeouf to give a talk on Saturday at the university in England, and the performance piece, branded with the hashtag #Elevate and broadcast online via a YouTube live stream, was part of his response.
Mr. LaBeouf said that he would still give a talk, but that he would also be on display inside the elevator for the 12 hours before and after it (aside from bathroom breaks). The performance piece was meant to “share the soapbox” with the less-famous people around him, he said on the live stream, as well as to defuse his anxiety about addressing an auditorium full of “geniuses.”
Whatever performance anxiety Mr. LaBeouf may have felt appeared to have dissipated in the more intimate, if fluorescently lit, space of the elevator (called a lift in Britain), where he chatted with small groups of visitors who waited as long as eight hours to make small talk with a movie star.
He was accompanied in the elevator, which served three floors during the performance piece, by the artists Nastja Säde Rönkkö and Luke Turner, with whom he has frequently collaborated, but Mr. LaBeouf did most of the talking.
As each group of gawkers came and went, there was one question that the actor, wearing a Disney sweatshirt turned inside out and leaning against the wall in one corner, said he was asked again and again:
“Why are you in the lift?”
Mr. LaBeouf said he understood why that particular question kept coming up. “It’s a weird thing,” he said to one visitor.
“I don’t have any celebrity friends,” he confided to another visitor (and the more than 10,000 people watching them online). “I have shame about that like I have shame about wealth. That’s why you’ll never find me in a Lamborghini.”
Mr. LaBeouf is no stranger to public attention (and peculiar public displays). A former Disney child star, he segued into blockbuster action movies as an adult before throwing himself into a kind of solipsistic performance art that both made statements about and was powered by his celebrity.
In 2014, he walked the red carpet at the Berlin premiere of his film “Nymphomaniac” wearing a tuxedo and a paper bag over his head that bore the message “I am not famous anymore.” He also wore a bag over his head during another performance piece that year at a Los Angeles gallery, where he later said a visitor sexually assaulted him.
A year later, he camped out in the Angelika Film Center in Manhattan for 24 hours to watch all 29 of his movies back to back and in reverse order. Members of the public were invited to watch him do that, too, via a live stream.
Mr. LaBeouf’s offstage persona can be as unpredictable as his art. Over the past 10 years he has had a series of run-ins with the law that frequently involved alcohol. In 2013, he was fired from a Broadway production of “Orphans” after castmates, including Alec Baldwin, complained about his volatile behavior.
None of that appeared to be on display on Friday, though, as Mr. LaBeouf politely greeted visitor after visitor to his boxy little stage.
He handed out slices of pizza, chatted about his favorite movies (“The Little Mermaid,” “Groundhog Day” and “Raging Bull”) and gave his thoughts on American politics (“It’s Bernie Sanders or nothing.”).
“What’s it like being a celebrity?” one young man asked.
“Sometimes it’s really cool, and sometimes it’s not so cool,” Mr. LaBeouf said. “There’s positives and negatives, like all things.”
Another visitor wanted to know what Mr. LaBeouf’s soul “consisted of,” but he did not answer.
For some fans, the experience of sharing an enclosed space with Mr. LaBeouf proved overwhelming.
One young woman from Brazil burst into tears as her time in the elevator came to an end, and Mr. LaBeouf hugged her as she wept.
“Drive safe,” he told her.
“I am very emotional in this moment,” she said between sobs. “It is weird to meet people who think like you.”
An earlier version of this article misstated the position of the elevator at Oxford University that was the site of Shia LaBeouf’s performance piece. It served three floors; it did not stay on one floor while he was in it.