Ever since her EP Vroom Vroom, released in 2016, Charli XCX has proven herself to be a pioneer of the future of pop music. Charli XCX’s unique embrace of PC Music—a record label known for its exaggerated and bizarre style of pop music—is taken to new heights on Pop 2, her second mixtape and most experimental yet.

“Tears”, featuring Caroline Polachek, is a captivating example of this musical style. Immediately, the listener is greeted by screeching synths joined by the distorted voice of Polachek and, later, Charli XCX. These increasingly dramatic vocal and instrumental effects enhance the emotion of “Tears”; starting in the second chorus, for example, haunting screams rise and fall in the background, making the song all the more heartbreaking. By the last 30 seconds, both singers’ voices have become so heavily autotuned their words are nearly indecipherable, but the emotion shines clearly through.

Pop 2 was released on Dec. 15. “Tears” is the fourth song on the mixtape.