Tragically, lifesaver Freddy Alamo was unable to reach one person inside, a teenager who died.
Alamo was in his home when he heard a blast that ripped through the Hunts Point area just after 3 a.m.
The unemployed painter saw the two-story home across the street at 846 Manida St. suddenly burst into flames, and he rushed into action.
He called 911, then sprinted down the stairs to the burning building.
"At that moment, I wasn't thinking about anything but getting in there," said Alamo, 39. "I know everybody in the building."
His sister-in-law, Lucy Rivera, lived on the top floor with her three kids, daughter-in-law and grandson.
Several other tenants lived below them.
Alamo could get no further then the front door, which was locked.
"I looked inside," he said. "I saw the stairs were in flames."
As a kid, Alamo often climbed trees and poles for fun. Now, in the wee hours of the morning, he grasped the side of the building and climbed up like Spider-man to save as many lives as he could.
Alamo knew Rivera's teenage daughter, Tiffany, slept in the upstairs bedroom facing the street. He scaled the stone exterior and banged on the window, calling her name.
"I didn't hear anything, so I came back down and I started banging on the [ground-floor] windows," he said.
As the residents who lived on the lower floor rushed out of the blazing building, Alamo and another neighbor, known only as Wilfredo, ran in and knocked on other doors.
"There was smoke everywhere," Alamo said.
Unable to climb the stairs, he said he "went to the back of the yard and climbed up [the outside of the building] to help them out."
He found Rivera's daughter-in-law, Jeanette Cruz, Cruz's husband, Christopher, and their 2-year-old son, Brandon in their smoke-filled apartment.
He helped them make their way to a balcony.
Firefighters arrived just in time.
They shoved a ladder up the back of the building, and Alamo handed the baby boy to a fireman.
Then he helped Jeanette down the ladder and Christopher followed.
"I'm very thankful that he was there," Jeanette said.
"He was the first one to show up. He helped me because I was really scared to go on the ladder.
"I was never afraid of heights. But this, trying to go over that ladder, I thought I was going to fall."
Rivera's son, Steven Santos, 17, who was in the front room where Tiffany usually stayed, died in the blaze - the cause of which was under investigation last night.
Tiffany, 15, had been at a friend's home.
Alamo had seen Steven the day before, playing video games.
"I told him, 'I'll see you tomorrow,' and I tapped him on his head. That was the last time," Alamo said.
"I felt bad. There wasn't much I could do. "There was no way I could have gotten into the front."
A heartbroken Lucy Rivera, who was also away when the blaze erupted, wept on a sister's shoulder.
"My son is gone," she cried. "I'm going to miss him so much."
Speaking of her heroic brother-in-law, she said, "I'm grateful he tried. If it wasn't for him, the whole family could have . . . "
And she couldn't even speak the word.