The Space Between Us (2015)

In a post-nuclear future, mankind tries to survive with the help of oxygen masks. High up in the mountains they have built a research centre in search of gills suited for mankind, so they can breathe freely once again and start a new life under water. Humble cleaner Juliette has her loyalties tested when she falls for Adam, a captive merman whose gills are mankind's last hope for survival.

The Space Between Us (2015)

www.thespacebetweenus2015.com
www.imdb.com/title/tt4697186/