It's been 20 years since the 9/11 attacks and the things that remind former Lt. David Lim of that fateful day aren't always so obvious.
Like a glimpse of a woman rushing through the city wearing sneakers, her high heels in hand.
"I saw this woman walk by carrying her shoes and all of a sudden I started getting chills and remembering those moments," Lim, 63, told TODAY of a recent experience in Manhattan that took him right back to Sept. 11, 2001, when the former police officer was running up the stairs of the World Trade Center's north tower as people blew past him, trying to escape.
"All these women were coming down, carrying their shoes," he recalled. "They were still in their sneakers. They hadn't changed yet because it was still early. It was just a really weird sight. And then, when I finally did get out, there were shoes all over the place."
Lim, who worked for the Port Authority Police Department's canine explosives unit, was in his office in the basement of the south tower when a plane struck the north tower, a harrowing experience he recounted to former TODAY anchor Katie Couric days after the attacks.
"I had just felt something shaking — even in the basement I could feel something," Lim told Couric, explaining that he then received a radio call for all units to respond, and rushed to the plaza area. "One of the carpenters advised me that there was a dead person on the plaza, in front of the stage. I didn't go out, I went to the window and saw the person and I called it in. As I'm calling it in, another body falls, about 50 feet away from that one. At that point, I realized this was getting more serious."
Lim didn't yet know that American Airlines Flight 11 had crashed into the building, dozens of floors above him. He headed upstairs to help, directing people down toward safety. He was on the 44th floor when he saw, through the windows, another plane crash into the south tower, sending what he described as a "fireball" toward the windows, knocking him and others backward.
He was on his way downstairs when the building collapsed, more than a hundred floors stacking on top of each other. Lim was trapped inside the rubble for nearly five hours before he was rescued, escaping with a concussion and mild injures.
"Some days, it's like it was yesterday," Lim said. "And some days, it's like an eternity."
Of course, it's times like these — the days approaching an anniversary — that make the events of 9/11 feel closer. It's also when he thinks most of the partner he lost: his police dog, Sirius.
"I remember the last thing I said to him was, 'You stay here, I'll come back and get you,'" Lim said, explaining that he put Sirius, a bomb-sniffing K-9, in his kennel before leaving the building to help.
When rescuers found Sirius' body in the rubble months later, they mistakenly thought they had found human remains, because one of Lim's shirts had fallen on the dog's body and they only saw blond hair sticking out from underneath, Lim said.
The death devastated him as well as his children, then 12 and 14, who knew the yellow Labrador well.
"These dogs come home with us," Lim said. "When I came home, the dog came with me. When I went to work, the dog went with me."
Early on, Lim was hesitant to admit how much the loss meant to him when speaking publicly, careful not to offend those who lost human family members in the terrorist attacks.
"I would kind of mention Sirius offhandedly — 'Yeah, and I lost my dog' — because I didn't want people to think I thought more of my dog than they did of their people," Lim said. "It was the doctors who told me, 'Listen, you have to accept the loss of your dog as your friend and your partner before you can move on. You got to stop saying, "Well, he's just a dog. Because he wasn't."'
He now knows the importance of honoring his late partner, the only K-9 to die in the attacks. Sirius is part of an exhibit at the 9/11 memorial in Manhattan, although he is not included on a wall with the names of the other fallen police officers. (This is a point of contention with Lim, as well as others, who believe that the K-9 should be honored like any other officer.)
However, Sirius does have a plaque at a memorial in Lynbrook, New York, not far from where Lim and his family live on Long Island, which he occasionally visits.
Today, Lim's children are all grown up: now 32 and 34, and Lim retired in 2014, after 34 years of service. Before the pandemic, he'd been spending his retirement following the New York Mets around the country, watching his baseball team play at different stadiums. He now spends most mornings at the gym, sometimes working out alongside other retired officers. They often chat about what it would be like to work in law enforcement today and how they would navigate the recent political divisiveness and anti-police sentiments, let alone the pandemic.
"So much has changed," Lim said. "We talk about it all the time, what it would be like. It would be difficult, to say the least. Everything now is under a microscope, for better or worse."
Lim wanted to be a police officer from a young age. He recalled talking to the officers who would come into the Chinese restaurant his parents owned in Queens for lunch when he was a kid.
“I was fascinated with their job because unlike in the movies or TV, these guys never took out their guns — or they never told me those stories,” he said. “It was always about helping people. They told me about CPR. Somebody’s heart would stop and they would bring them back to life. I was like, ‘Wow!’”
Another time, when Lim was maybe 12 or 13, he was riding a new bicycle at the park when a bigger kid approached him and demanded he hand over the bike. A police officer helped him get his bike back and took the bully home to his mother — a “seminal moment” Lim says he’ll never forget, and one that sealed the deal in his mind that he wanted to be a police officer when he grew up.
“I wanted to one day give back on that one,” he said.
Now that he’s retired, he feels his duty lies in keeping the memory of Sept. 11, 2001 and the heroes who died that day, including his pal Sirius, alive. He’s well aware that some young adults today weren’t even born yet when the attacks happened.
Shortly before he retired, a young officer knocked on his door with a question.
“He said, ‘I was watching the History Channel the other day and there was this guy, he opened up the stock exchange after 9/11 and he looked just like you. Do you have a brother?’” Lim said of the exchange. “I go, ‘That was me.’ He said, ‘No way! You were there?’ So then I’m sitting there going, ‘I’m on the History Channel. I’m officially old.’”
Moments like those are only further proof to Lim that it’s important to share what he survived: “There are people that weren’t even born yet that are going to see this,” he said. “They need to know at least part of my story.”