Don't text your ex when your lying in bed with your current beau-thing. That's one of those cardinal rules of relationships that should go without saying, but it seems someone didn't read the user manual before getting into it with London singer Anne-Marie.

That's pretty messed up, but it works out for us, because the vocalist turned all that anger into “Alarm,” a trapped-out pop anthem for pissed off girlfriends everywhere. Of course, when someone hurts you, you've got to hit them twice as hard, so Anne-Marie gave the stems over to Marshmello and he smoked the ooey-gooey bits until they melted into a certified banger.

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“Karma is a bitch,” Anne-Marie warns as Marshemello's builds the beat with enough hot handclaps and heavy bass to match the fury of a woman scorned. When the drop finally hits, she's already gone, out of the door, and on her way to the next one. This dude shouldn't have messed with a bad one like Marie, but it sure is nice to see Marshmello mess with a tune like this.