WARNING! Spoilers ahead for Stranger Things season 4, volume 1.

Kate Bush's "Running Up That Hill" has quickly become a number 1 hit after featuring in Stranger Things season 4, volume 1, accompanying Max Mayfield's escape from Vecna, for a few reasons. The song is a classic '80s anthem and the favorite song of Max, who listens to it several times throughout the season. "Running Up That Hill" has become even more popular than the many classic '80s songs in Stranger Things seasons 1-3.

After the deaths of Chrissy Cunningham, Fred Benson, and Patrick McKinney, Max Mayfield (Sadie Sink) becomes the next victim of Vecna, the evil entity in the Upside Down, otherwise known as "001." After researching Victor Creel (Robert Englund) and his family's demise at the hands of Vecna, the gang realizes that emotional attachment to music can help a victim resist Vecna's touch, which would otherwise kill them. By listening to her favorite song, Max makes an emotional escape from inside her own mind (in the Upside Down) back to her friends, Dustin Henderson and Lucas Sinclair. She continues to listen to it in the hope that it will allow her to resist Vecna's influence, which seems to work as he moves on to tormenting Nancy Wheeler (Natalia Dyer). In the real world, the song has reached number 1 in the UK and Australian charts and the top 5 in the US charts.

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"Running Up That Hill" is unique in the pantheon of Stranger Things songs as it is used directly to further the plot, both in-universe and out of the universe. Stranger Things has always had an amazing soundtrack full of '80s hits, such as Bon Jovi's "Runaway," which is used when Nancy Wheeler and Jonathan Byers leave Hawkins to meet Murray Bauman in season 2. However, unlike in that instance, "Running Up That Hill" carries important context rather than just serving as part of the soundtrack, making it far more impactful.

Sadie Sink as Max in Stranger Things season 4

The emotional weight that accompanies Max's escape from Vecna makes the song's use very powerful in the scene. Sadie Sink's performance, paired with the slow-motion cinematography and the epic use of Bush's music, make for an unforgettable sequence. Stranger Things season 4 dials up the horror with Vecna, implying that Max could die at this point. With this music playing, Netflix watchers are led to believe that this is the end for Max, cementing the song's association as a traumatic, memorable moment in Stranger Things season 4.

Kate Bush is mentioned several times within the dialogue throughout the season, such as when Lucas confirms that he too is (now) a fan of hers. The consistent mentioning of Bush and Max's constant playing of the song to keep Vecna at bay reminds audiences of its importance, increasing its popularity even further. It also marks the second time Stranger Things confirms a character's favorite song after Jim Hopper expresses his affection for Jim Croce's "You Don't Mess Around With Jim" while bonding with Eleven in season 2. All of these factors have made "Running Up That Hill" synonymous with Stranger Things season 4, with the song even being used in Netflix's trailer for the upcoming season 4, volume 2.

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Stranger Things season 4, volume 2 releases on Netflix on July 1.

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