The highly anticipated "Yayoi Kusama: Infinity Mirrors" at the Hirshhorn showcases the Japanese artist's 65-year career for the first time in Washington, D.C. (Erin Patrick O'Connor/The Washington Post)

Pass holders waited for more than 90 minutes outside the Hirshhorn Museum and Sculpture Garden on Saturday to gain entry into the much-anticipated exhibition “Yayoi Kusama: Infinity Mirrors.”

Once inside, they waited again, and again, and again.

The backup started about noon and continued until the final time slot at 4 p.m. The museum will stay open until 7:30 p.m., two hours later than planned, to accommodate the crowds.

The Hirshhorn introduced the free timed passes to try to eliminate long lines to get into the exhibits, which features six immersive mirror rooms. Despite a burst of heavy wind and rain, most ticket holders waited in often-confusing lines. Harried staffers tried to organize the throngs but struggled without signs or loudspeakers.

District residents Prajakta Chitre and Goran Vojvodic waited for almost two hours to get same-day passes, then went to brunch and returned at 1:30 p.m. They waited 90 more minutes to get inside the museum.

“We expected to wait in the morning, but we didn’t expect to wait (again),” Chitre said.

Once inside, there were more lines. Hundreds were queued up on two floors waiting to enter the gallery. Once inside, there were more lines for the mirror rooms. Instead of each person getting 30 seconds inside, museum officials were arranging strangers into groups of four for 20 seconds.

“Infinite rooms,” Maddy Vogel muttered.

It was the first weekend for the much-hyped show, and museum officials said visitors were staying longer than anticipated. New visitors weren’t allowed in until earlier guests left. And one of the main attractions, the final mirror room, was closed for repairs.

Deputy director Elizabeth Duggal said the museum was assessing its policies for Sunday and would probably offer fewer same-day passes to reduce the crowds and wait. Passes for next weekend have already been distributed, but the number for March 11-12 will probably be reduced, she said.

Sandor Axelrod arrived at 2:30 p.m. with his 3 p.m. pass, because the ticket suggested holders arrive a half-hour early. He entered the building at 4:30, and the gallery 20 minutes after that.

Axelrod was surprised that most people decided to wait. “People are pretty upbeat. Some complained, especially when it rained, but for the most part they are sticking it out,” he said. “They seem excited to get in.”