Deputy Chief Joe Herbert is credited with cracking some of this city's biggest cases over the past four decades. "It's a gratifying job, a rewarding job, but a dangerous job," Herbert said. "I've had a great career." Chief Joe Herbert enjoyed early success, cracking his first big case after just about three years on the job. ". "The trick is to know the evidence, master the evidence," Herbert said. Herbert reached a new level of notoriety in the 1990s, when he solved the mystery of New York City's Zodiac Killer, a copycat of a California serial killer. Herbert had worked the case for years without luck. Then, while working as a hostage negotiator, he arrested Heriberto Seda, who had shot his half-sister and was hiding in his New York City apartment. Seda wrote a confession, and Herbert recognized the writing as similar to letters written by the Zodiac Killer. "I think it was fate," he said. "It came to me. I didn't come to it. At the bottom of the letters, he makes a strange symbol." Herbert said he saw that symbol and knew. "It was actually was a calm feeling, because I knew I had him," he said. After the 9/11 terror attacks on World Trade Center, the NYPD called on Herbert to help intercept terrorist threats to the city. "I was one of the first 25 to go in as a lieutenant into the JTTF," Herbert said. "The threat is constant since 9/11. I think it's 17 to 18 investigations that we disrupted for the most part." Among those threats, the 2016 Chelsea bombing stands out to Herbert. He responded to the scene that night. "There was a lot of power in that bomb, and we are very fortunate nobody got killed," Herbert said. For all his notoriety, Herbert said he's most proud of playing a role in reducing the city's homicide rate and ultimately making New York a safer place to live. "Going out every day chasing bad guys, it came at a high cost," Herbert said. "A lot of blood, sweat and tears." Herbert said that in his time on the force, he has lost 160 comrades who were killed in the line duty and lost another 138 to 9/11-related cancers. "That's a lot of friends to lose," Herbert said. "But you've got to keep going." At 60, Herbert said health concerns are forcing him to take a step back. "I don't want to leave, but it's time," he said. A little known secret is that Herbert almost never became a police officer. "I wasn't going to take the job," he said. "I had a job making a lot more money at the time. It was his father, he said, who convinced him of the importance of a pension and public service. "It turned out to be the best thing that ever happened to me," Herbert said. "The greatest compliment I can give to Joe is, if something happened to me or my family, I'd want Joe Herbert leading that investigation," NYPD Chief of Counter-terrorism James Waters said. Waters and Herbert both started with the NYPD in 1981. Waters said Herbert has been more than a colleague. "Joe Herbert is a friend," he said. "He is a remarkable guy."