The song was produced by Daptone Records' Wayne Gordon, who also helped create another of Isolation
's ballads: "Flight 22". Uchis ended up dropping the video for "Loner" around the time they were working together, which Gordon drew inspiration from while working on "Killer."
"I would play that video on mute and I would manipulate the music and make this piece while I was watching that video," he explained to Genius
, adding that he was also inspired by the classic David Lynch drama Mulholland Drive
. "You feel like doom is right around the corner but you don't know when, but you're pretty much in this dream state the whole time. I wanted to create that feeling with that song."