Horrifying new video has emerged of the moments leading up to a devastating crash that claimed four lives at a Long Island nail salon, including a police officer getting her nails done before her wedding.

The chilling footage shows ex-Marine Steven Schwally, 64, looking visibly disheveled as he purchased alcohol at a liquor shop, before embarking on his deadly rampage.

Schwally can then be seen speeding through a parking lot, narrowly avoiding pedestrians in the footage obtained by Newsday, before charging full-speed into Hawaii Nail & Spa in Deer Park on June 28.

The former Marine allegedly said he had consumed 18 beers before getting behind the wheel and reaching speeds of 78mph before plowing into the salon.

Prosecutors say that Schwally’s speech was slurred, his eyes were bloodshot, and his breath reeked of alcohol at the time of his arrest.

The crash claimed four lives, including that of an off-duty police officer, Emilia Rennhack, 34. 

The three other victims were named as 37-year-old Jiancai Chen, the owner of the salon, and employees Yan Xu, 41, and Meizi Zhang, 50.

Nine other people were injured including a 12-year-old girl.  

Schwally allegedly told officers after the crash: ‘I haven’t broken any laws. Can I get my license back? I’m a Marine.’

On Thursday, Schwally pleaded not guilty to a 38-count indictment including charges of murder and vehicular manslaughter.

Schwally faces a potential life sentence if convicted of the top charges.

The video appears to show no deceleration at all as Schwally’s 2020 Chevy Traverse barrels down the road opposite and into the car lot before hitting the salon.

The sound of screams can be heard from the salon and customers from the neighboring business can be seen running out of their store to see what had happened.

Prosecutors described the crash as having occurred with the driver having ‘accelerated at a high rate of speed’, and that Schwally allegedly: ‘Drove in the opposite lane of travel, nearly striking pedestrians.

‘He continued through the intersection, went airborne’ as he slammed into the packed nail salon.’

The car was only brought to a halt by the back of the building after destroying everything in its path.

This is not Schwally’s first time being charged with driving while intoxicated, Newsday reports.

Back in April 2014, he pleaded guilty to driving under the influence and had his license suspended.

Schwally’s brother Edward also claims he has had more than one prior DUI, recounting how he once drove his brother to probation after he refused to take a breathalyzer in 2010 or 2011.

‘It’s like my worst nightmare come true,’ the brother told The Post.

‘I feel terrible about innocent people getting hurt.

He also admitted his brother had a habit of ‘bad mouthing everyone’.

‘He could be vicious at times,’ he added.

‘I mean I feel terrible for him that it ended up happening. There’s nothing I can really do for him. It’s out of everybody’s hands. It’s in the hands of the courts.

‘He is not going to see the light of day. He’s finished. There is no way to get out of that.’

The nail bar’s clients have reacted with horror to the graphic footage with some demanding the driver receive a life sentence.

‘I’m terribly sorry for all you have had to endure,’ wrote Christopher Steven. ‘Hang in there nail salon ladies. Justice will be done.’

‘Omg this is insane. They had no chance,’ wrote Jenny Lynne.