Pedalling furiously, racing the wrong way down one-way streets, a Boston Pedicab driver has emerged as an unlikely unsung hero of the marathon bombings, ferrying a surgeon to the hospital when no one else could.

“You can get these things through traffic anywhere,” said Boston Pedicab driver Nicholas Viau. “You can hop over sidewalks, you can get in the smallest little areas.”

After the bombs went off on Marathon Monday, the cops had ordered Viau out of the Back Bay. He was headed back to Boston Pedicab’s shop in the South End when good fortune placed him in the path of someone who needed to be somewhere fast.

Dr. Jeffrey Kalish, Boston Medical Center’s director of endovascular surgery, had the day off to watch his wife run the marathon. After the bombs went off, his surgery team called. They needed him. Now.

“What they needed was more vascular surgeons that could handle blood vessel problems, amputations, just all of the things that they started to hear was going to be coming into the ER,” Kalish said. He hopped in a friend’s car.

They were less than two miles from BMC, but the streets were jammed. Kalish got out and started walking. But every minute counted. People’s lives and limbs depended on it. Then he saw the big bright green trikes.

“I figured that was going to be my quickest ticket in,” Kalish said. “I said, ‘Hi, my name is Jeff, I’m a vascular surgeon at Boston Medical Center,’ and one of them was nice enough to put me in his pedicab and we rode off.”

Viau wasn’t supposed to be taking riders. But when he heard who Kalish was, he ushered him into his cab.

Kalish described the wild emergency ride:

“I don’t think we even thought about the lights. I don’t think we thought about the one ways because there was no one on the roads.”

Away from Copley Square, the streets were “eerily quiet” and empty.

“I think we were flying,” Kalish said. “Definitely I know we were going the wrong way down East Newton Street.”

Viau said, “I figured, extenuating circumstances, you do what you have to do.”

“I had no idea what I was going to see,” Kalish said about the job ahead. He had hours of grueling surgery ahead of him.

They arrived at the hospital in minutes. With a handshake and a quick “good luck” from Viau, Kalish made his way into the operating room. “I wasn’t winded … physically I was in perfect shape.”

His patient had severe injuries to both legs, but Kalish was able to save them.

“That was one of the most awful days as a surgeon,” Kalish said. “My patient was the last one out of the operating room … it took a long time to get control of everything.”

But thanks to a Boston Pedicab driver, he was there when he was needed. “Nick,” Kalish said, “thank you very much.”