The Chainsmokers' DJ was cheating on his girlfriend and she released footage to prove it.

“They’ll look you in the eyes and tell you they love you. Then destroy you without a second thought,” Tori Woodward posted to Instagram on Tuesday.

Woodward is (supposedly) the now-ex-girlfriend of Alex Pall, a Grammy-winning DJ and one half of the pop duo The Chainsmokers.

Her words were written over grainy CCTV footage of Pall kissing another girl,  posted to Woodward’s Instagram story. “Alex is disgusting. Men are trash. Don’t ever forget it,” she wrote.

We’re not quite sure how she came to be in possession of the CCTV footage, taken outside what appears to be residential apartments (we’re sure Pall is just as surprised as we are) but, even still, we can’t look away.

The pair have been dating since February 2014, People reports and, according to Woodward's subsequent posts, this isn't the first time Pall, 32, has been unfaithful.

His former trysts came to light after the discovery of the footage.

Listen: The Mamamia Out Loud team explain the latest trend in infidelity: microcheating. Post continues after.

"After hours of begging him for scraps of honesty, I chipped away just enough to confirm that this is not the first time he’s cheated on me," Woodward wrote.

She said she discovered there had been "countless others he looked me in the eyes and swore on his life he never touched."

A post shared by Tori Woodward (@toriwoodward) on Feb 8, 2016 at 4:52pm PST

Pall started The Chainsmokers in 2012 and, soon after, Andrew "Drew" Taggart, 28, came on board.

They shot to fame in 2014 with their single #Selfie and, more recently, achieved Grammy success with the 2016 hit Don't Let me Down and topped charts with Closer in the same year.

Pall has not yet responded publicly to Woodward's allegations. However, only hours ago he posted to Instagram a preview of the duo's latest single, which dropped today, called I am the Sick Boy. (Convenient timing, no doubt.)

The song's lyrics, including "I live in a prison/That I built myself" and "Welcome to the narcissism", seem ironically fitting considering Pall's treatment of his former relationship.

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