This contemplative track was written for The Divergent Series: Insurgent movie and features on the film's accompanying soundtrack. It sees M83 mainman Anthony Gonzalez teaming up with Haim. "We've been fans of Anthony Gonzalez and M83 for a long long time so when he reached out to have us sing on the song we were ecstatic," the girl group told MTV News of the collaboration. "We had the best time in the studio with him, it all happened so fast and was so easy and natural. We are so excited to be a part of this movie."
M83 have been involved with the Divergent franchise before. Their track "I Need You" appeared on the soundtrack for the first film, Divergent, which was released in 2014.
The third verse of "Mmm Mmm Mmm Mmm" by Crash Test Dummies ("they shook and lurched all over the church floor...") was inspired by girl whose parents would speak in tongues at their Pentecostal service.