It's the deadliest drug in America shipped from Mexico and China: fentanyl, a synthetic opioid 30 to 50 times more potent than heroin.
Ray Donovan is the New York Special Agent of the Drug Enforcement Administration Field Office.
"Two milligrams are considered potentially deadly," says Donovan.
This year, his office seized a record 540 million 1-milligram dosage units, enough to kill the entire city
"This essentially means that thousands and thousands of lives have been saved," says Donovan.
Expecting tourists to flood the city on New Year's Eve, the DEA fears many unsuspecting people are in danger of coming into contact with the deadly drug.
"There are many people coming from the city to celebrate here," says Donovan. "It's an opportunity for a drug trafficker or a dealer to pass drugs on to these users and they may think they are getting a certain drug, but in fact they get fentanyl."
New York is a hub for fentanyl sales in the northeast.
"We often see large amounts of heroin and fentanyl coming into town and being distributed all the way northeast to Maine as far as DC and West Virginia," Donovan says.
There were several high-profile deaths associated with the synthetic opioid – originally developed to treat end-stage terminal cancer patients.
In 2016, Prince died after taking a fatal dose of fentanyl.
The toxic mixture of cocaine and fentanyl led to the death of popular rapper Mac Miller.
Most drug users believe that they buy pure cocaine or pure heroin, but it can not go further from the truth.
So why? Drug dealer whose number is on The goal of earning money to sell a deadly cocktail that could kill its customers?
"It's about competition in the market," says Donovan. "Making and making your narcotics stronger means the user wants to come back. You become addicted faster.
And it shows: The most recent statistics released by the state increased the number of opioids from 2015 to 2017 by 60 percent.
Nationally, almost 60 percent of all overdoses were opioids.