Kansas City, Mo. ? The defensive coordinator of the Kansas City Chiefs barely speaks above a whisper. Glasses tend to slide down the bridge of his nose. He has a habit of staring into space whenever he’s answering a question and can drone on for an interminable amount of time.

He gives off a librarian’s vibe, or perhaps that of an algebra teacher — certainly not of a mad scientist orchestrating one of the most feared defenses in the NFL.

His name is Bob Sutton. And yes, he is.

Under his dazzling wizardry, the Chiefs have yet to allow more than 17 points in a game during a 7-0 start, the second-best in franchise history.

They’re on pace to set the NFL record for sacks in a season. They’re tops in the league when it comes to stopping opponents on third down, and in the red zone. They are also the best when it comes to taking away the ball.

Strange to think that when new Chiefs coach Andy Reid hired Sutton away from the New York Jets in the offseason, hardly any players on the team had even heard of him.

“I read a little about him,” Pro Bowl linebacker Tamba Hali said. “He’s just a real humble guy. He didn’t seem like he was coming in to change people’s position. He installed his system and asked you to buy into it. And we probably wouldn’t be here if we didn’t.”

Hali quickly learned that beneath Sutton’s placid demeanor was a guy who burned to win. He relishes finding the smallest weakness in an offense and then exploiting it. He takes glee in the idea of terrorizing a quarterback or making life miserable for a running back.

“You could tell he loves his job,” Chiefs safety Eric Berry said. “Just talking to him, you see how much he loves the game. He has passion for it. We just had a meeting for two hours, and he was excited about the game plan the whole two hours, so that gets us fired up.”

Sutton started his career a graduate assistant under Bo Schembechler at Michigan, and spent his first three decades in coaching in the college ranks. He bounced through Syracuse, Illinois and North Carolina State, among other places, before finally landing at Army.

That was his first and only head coaching job, and it was mostly a success. He went 10-2 in 1996 and had the Black Knights in the Top 25. To put that into context, the program has had just one winning record — a 7-6 finish in 2010 — since that season.

“There’s no question that he’s a brilliant man,” said Purdue coach Darrell Hazell, who was an assistant under Sutton at West Point. “So many people see things from one angle, but Bob always had that special quality to see things from so many different angles.”

Sutton transitioned to the NFL in 2000 as the linebacker coach of the Jets, and rose through the ranks to become defensive coordinator on Eric Mangini’s staff. When Mangini was fired and Rex Ryan took over, Ryan persuaded Sutton to stay on as a defensive assistant.

“It was one of those things where he said, ‘OK, I’ll give it a shot and stay,'” Ryan said. “He was the assistant head coach and it was awesome. I really leaned on him.”

His players embraced him, too, and were devastated to see him go.

“I still text with him every week,” Jets linebacker Calvin Pace said. “For the linebackers, he was almost like a father figure to us. We’d sit with him and talk with him. A lot of times, it wasn’t even about football. We were just talking. He’s just a really, really good guy.”

Reid had known about Sutton when he was still in Philadelphia, and asked unsuccessfully for permission to interview him. But when he took over the Chiefs, Reid made another run at him to be his defensive coordinator, and this time Ryan knew he had to let Sutton go.