Before acting, Hernandez played the cello in several bands. In 2013, she made her debut in Machete Kills. She was cast in the ABC television series Members Only, also known as The Club, before it was cancelled in 2014. In 2016, she starred in Blair Witch and had a supporting role in La La Land.
As of 2016, Hernandez has played Samantha in the TV series Graves. In 2017, she co-starred in the sequel to Prometheus, Alien: Covenant. She will appear in Under the Silver Lake, completed and scheduled for a 2018 release.
