Varèse Sarabande will release the Z for Zachariah – Original Motion Picture Soundtrack digitally August 28 and on CD on September 4, 2015. The album features the original music composed by Heather McIntosh.

"This is my second time working with Craig Zobel, so our director-composer language is pretty well developed," explained McIntosh. "With our last collaboration, the ensemble was super minimal, super biting, but minimal. This time we wanted to push ourselves with the score and it's thematic development. Really go for it, you know? Though it is a chamber work, we wanted the sound to be full and orchestral."

McIntosh had the opportunity to write for organ in a scene where Margot Robbie's character plays the instrument on screen. "We knew that we needed to get the tone of this right. It needed to feel like a timeless hymn and also be a defining theme for Ann. I started working on this after reading an early draft of the script, long before the film was shot," McIntosh described.

"This work has a very pastoral tone, even though we are depicting the end of the world, it takes place in the only part of the world unaffected by the apocalypse," said McIntosh. "Along with lush chamber strings and horns, there is also a subtle underlying tension developed by the use of electronic and acoustic manipulated sounds."

Roadside Attractions presents Z for Zachariah in theaters August 28, 2015.