Songfacts®:

• This song is about the peculiar alchemy of producing a child. Death From Above 1979 drummer/vocalist Sebastien Grainger was inspired by the birth of his daughter.
  
  "Having kids is a revelation to the person that is having the kid, and it's always novel and exciting and new," he explained in a Songfacts interview. "That's what keeps the human project going: It's surprising and new and exciting to everybody."
  
  He added: "Before my daughter was a person, when she was a concept and then a thing in progress when we were anticipating her. As a scientific pursuit, the idea of mixing your DNA with someone you've known for so long, going, 'Wait a second. We can mash our DNA together, and then make another person that is a combo of the both of us?' is magic, really. So, that song is an exploration of that. It's the exploration of the equation of making new people."
• Death From Above 1979 is the Canadian rock duo of Grainger and Jesse F. Keeler, who plays an assortment of instruments. "One + One" was the lead single from their fourth album, Is 4 Lovers.
• The video was directed by Eva Michon and shot in four different fields in Marmora, Ontario, including one at Keeler's farm.
• Sebastien Grainger's wife, photographer Eva Michon, became pregnant around the time he started working on the song. He told American Songwriter that after hearing an early version she suggested making it "dancier,'" so Grainger went back into the studio and re-did the drums.
  
  "As the record was taking shape, every time I would come home from the studio, the baby would start dancing in Eva's belly," he added. "Even before I walked in the room, the party would start. One plus one is three - that's magic!"