The film is notable for being loosely based on, as well as using footage from, Mamoru Oshii's 1985 OVA, Angel's Egg.

As Frank struggles to survive, the angel appears to him in a vision, as she grapples with the consequences of using her power to rescue a human race that may not deserve to be saved.

In the Aftermath was shot on a low budget, and used live-action segments in order to pair it with footage from Angel's Egg, which the studio acquired in a distribution bundle, and ended up paying very little for the rights to.

[1][2] Neither director Colpaert nor producer Tom Dugan understood the original film, calling it "incomprehensible," and opted to shoot live-action segments in order for it to make more sense to audiences.

[1] The live-action portions of the film were shot at the abandoned Kaiser Steel mill in Fontana, California.