Then came a moment of what he suspects was divine intervention.
Now Daniel Reiser hopes others can learn from his ordeal.
The youngster was "wet and frozen" from a morning soccer game when they pulled into the parking lot of the Chase Bank on County Road near Central Avenue in Tenafly around 11:30 a.m. Saturday, April 2, Reiser said.
"I went into the ATM vestibule just a few feet in from my car," the 48-year-old father of four wrote in an account of the incident. "I left the car idling to keep the heat on for him."
As he waited for his cash, Reiser said, he saw his Audi A8 backing out of the parking space. He ran outside to find "a guy in the driver’s seat pulling away with my son in the back seat."
"I try the door, but he locked it," said Reiser, a trained actor and director who has studied at NYU, Playwright Horizons and the prestigious Lee Strasberg Theatre Institute and works as vice president for a Jersey City real estate developer.
"I hold onto the door screaming, 'No!, No!! What are you doing!? Please, NO!' he said. "He drives and drags me over the curbside and into the bush and drives away."
Bloodied from the fall, Reiser -- who also happens to be a marathon runner -- said he began chasing the car on foot, shouting: "My son, my son!!' "
"He speeds away past the drive-through ATM and down Central Ave," he said.
"I keep in pursuit screaming at the top of my lungs," Reiser said. "A Good Samaritan driving down the street witnesses this and starts driving after him on the wrong side of the street."
He continued:
"The criminal speeds through the 4-way intersection with wreckless abandon at Piermont [Road] and over the tracks towards the middle school.
"I am running in hot pursuit thinking my son is gone!! That I will never see my son again!! The car kept going. I kept running.
"Luckily, like [G]od was watching over him, the car stops and the criminal abandons my car with my son inside and gets into another vehicle and speeds off. I get to the car to check my son and felt so blessed to be able to hug him again!! I called the police and filed a report."
The thief had gotten into a trailing BMW SUV that had been seen prowling neighborhoods earlier, Tenafly Police Capt. Michael deMoncada said.
He and an undetermined number of accomplices tested car door handles and then moved on when they found them all locked, the captain said.
The thieves ended up at the bank around 11:30 a.m. -- around the same time that the dad headed in.
SEE: Frantic Father Runs Down Street After Car Thief Who Fled With Young Son In Back Seat
“Our officers and detectives have been in contact with local and regional law enforcement partners and have issued a BOLO [Be On the Lookout] alert for the suspect BMW SUV,” deMoncada said after the father and son were reunited.
"We are fortunate that the thief was smart enough to safely stop and flee the area once he realized there was an innocent child in the car," the captain said. "However, that does not make this incident any less traumatic for the victims or less serious for responding officers.”
The still-shaken Reiser shared his story on Facebook later on Sunday. He was still emotional Monday night during a News4 New York interview outside the bank (SEE: Dad Describes Moments His Car Was Stolen With 11-Year-Old Son Inside).
His goal, he said, was "bringing awareness to a growing and troubling problem."
"The criminals seem so brazen! I mean this happened on a Sunday afternoon at 11:30 am in a busy parking lot," he wrote.
Car thefts not only have skyrocketed throughout New Jersey the past few months. They also occur during the day now -- all because of new rules that prevent police pursuits.
The directives issued by the New Jersey Attorney General's Office just a few months ago prohibit police from pursuing drivers who haven't already presented a "clear and serious threat" beforehand.
Speed or evasive driving doesn't cut it.
Add that to a New Jersey bail reform law that requires local authorities to release all but the most violent offenders.
The result is what many agree is the highest concentration ever of thieves from out of the area swiping the most expensive vehicles from the suburban New Jersey streets.
Despite having their hands tied, Tenafly police and their colleagues everywhere are "dedicated to doing everything within our legal authority to catch these criminals and see they are brought to justice,” deMoncada said.
The still-shaken Reiser agreed.
Borough police "were kind and gentle with me and my son during this stressful and surreal ordeal," he said. "They are consummate professionals who have the best interest at heart for our town."
The father said he hopes that those responsible are brought to justice. "I would hate for anyone to go through that moment when you think your son is gone," he said.
It's a genuine threat, deMoncada said.
“It seems that the majority of people are heeding our warnings to keep their parked vehicles locked," he said. "Unfortunately, it seems the criminal element is changing their tactics by targeting unattended vehicles left running outside of businesses.”
A Cresskill resident who frequents the Chase ATM -- often after hours -- said he frequently sees customers who "keep their cars unlocked and running all the time."
"I always wanted to say something to these people about how dangerous that is but never did," he said. "I hope people read this and understand that this is not something they want to do consistently. It only takes one time before it becomes a tragedy."
Having learned his lesson, Reiser agreed. He urged others to "please be safe and be on the lookout for suspicious individuals and vehicles perusing our streets.
"I would hate for anyone else to have to go through this ordeal with their family or loved ones."
Click here to follow Daily Voice Pascack Valley and receive free news updates.